1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697
// This file is part of Substrate.
// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//! Support code for the runtime.
//!
//! ## Note on Tuple Traits
//!
//! Many of the traits defined in [`traits`] have auto-implementations on tuples as well. Usually,
//! the tuple is a function of number of pallets in the runtime. By default, the traits are
//! implemented for tuples of up to 64 items.
//
// If you have more pallets in your runtime, or for any other reason need more, enabled `tuples-96`
// or the `tuples-128` complication flag. Note that these features *will increase* the compilation
// of this crate.
#![cfg_attr(not(feature = "std"), no_std)]
/// Export ourself as `frame_support` to make tests happy.
#[doc(hidden)]
extern crate self as frame_support;
#[doc(hidden)]
extern crate alloc;
/// Private exports that are being used by macros.
///
/// The exports are not stable and should not be relied on.
#[doc(hidden)]
pub mod __private {
pub use alloc::{
boxed::Box,
rc::Rc,
vec,
vec::{IntoIter, Vec},
};
pub use codec;
pub use frame_metadata as metadata;
pub use log;
pub use paste;
pub use scale_info;
pub use serde;
pub use serde_json;
pub use sp_core::{Get, OpaqueMetadata, Void};
pub use sp_crypto_hashing_proc_macro;
pub use sp_inherents;
#[cfg(feature = "std")]
pub use sp_io::TestExternalities;
pub use sp_io::{self, hashing, storage::root as storage_root};
pub use sp_metadata_ir as metadata_ir;
#[cfg(feature = "std")]
pub use sp_runtime::{bounded_btree_map, bounded_vec};
pub use sp_runtime::{
traits::{AsSystemOriginSigner, AsTransactionAuthorizedOrigin, Dispatchable},
DispatchError, RuntimeDebug, StateVersion, TransactionOutcome,
};
#[cfg(feature = "std")]
pub use sp_state_machine::BasicExternalities;
pub use sp_std;
pub use sp_tracing;
pub use tt_call::*;
}
#[macro_use]
pub mod dispatch;
pub mod crypto;
pub mod dispatch_context;
mod hash;
pub mod inherent;
pub mod instances;
pub mod migrations;
pub mod storage;
#[cfg(test)]
mod tests;
pub mod traits;
pub mod weights;
#[doc(hidden)]
pub mod unsigned {
#[doc(hidden)]
pub use crate::sp_runtime::traits::ValidateUnsigned;
#[doc(hidden)]
pub use crate::sp_runtime::transaction_validity::{
TransactionSource, TransactionValidity, TransactionValidityError, UnknownTransaction,
};
}
#[cfg(any(feature = "std", feature = "runtime-benchmarks", feature = "try-runtime", test))]
pub use self::storage::storage_noop_guard::StorageNoopGuard;
pub use self::{
dispatch::{Callable, Parameter},
hash::{
Blake2_128, Blake2_128Concat, Blake2_256, Hashable, Identity, ReversibleStorageHasher,
StorageHasher, Twox128, Twox256, Twox64Concat,
},
storage::{
bounded_btree_map::BoundedBTreeMap,
bounded_btree_set::BoundedBTreeSet,
bounded_vec::{BoundedSlice, BoundedVec},
migration,
weak_bounded_vec::WeakBoundedVec,
IterableStorageDoubleMap, IterableStorageMap, IterableStorageNMap, StorageDoubleMap,
StorageMap, StorageNMap, StoragePrefixedMap, StorageValue,
},
};
pub use sp_runtime::{
self, print, traits::Printable, ConsensusEngineId, MAX_MODULE_ERROR_ENCODED_SIZE,
};
use codec::{Decode, Encode};
use scale_info::TypeInfo;
use sp_runtime::TypeId;
/// A unified log target for support operations.
pub const LOG_TARGET: &str = "runtime::frame-support";
/// A type that cannot be instantiated.
#[derive(Encode, Decode, Debug, PartialEq, Eq, Clone, TypeInfo)]
pub enum Never {}
/// A pallet identifier. These are per pallet and should be stored in a registry somewhere.
#[derive(Clone, Copy, Eq, PartialEq, Encode, Decode, TypeInfo)]
pub struct PalletId(pub [u8; 8]);
impl TypeId for PalletId {
const TYPE_ID: [u8; 4] = *b"modl";
}
/// Generate a [`#[pallet::storage]`](pallet_macros::storage) alias outside of a pallet.
///
/// This storage alias works similarly to the [`#[pallet::storage]`](pallet_macros::storage)
/// attribute macro. It supports [`StorageValue`](storage::types::StorageValue),
/// [`StorageMap`](storage::types::StorageMap),
/// [`StorageDoubleMap`](storage::types::StorageDoubleMap) and
/// [`StorageNMap`](storage::types::StorageNMap). The main difference to the normal
/// [`#[pallet::storage]`](pallet_macros::storage) is the flexibility around declaring the
/// storage prefix to use. The storage prefix determines where to find the value in the
/// storage. [`#[pallet::storage]`](pallet_macros::storage) uses the name of the pallet as
/// declared in [`construct_runtime!`].
///
/// The flexibility around declaring the storage prefix makes this macro very useful for
/// writing migrations etc.
///
/// # Examples
///
/// There are different ways to declare the `prefix` to use. The `prefix` type can either be
/// declared explicitly by passing it to the macro as an attribute or by letting the macro
/// guess on what the `prefix` type is. The `prefix` is always passed as the first generic
/// argument to the type declaration. When using [`#[pallet::storage]`](pallet_macros::storage)
/// this first generic argument is always `_`. Besides declaring the `prefix`, the rest of the
/// type declaration works as with [`#[pallet::storage]`](pallet_macros::storage).
///
/// 1. Use the `verbatim` prefix type. This prefix type uses the given identifier as the
/// `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", verbatim_attribute)]
///
/// 2. Use the `pallet_name` prefix type. This prefix type uses the name of the pallet as
/// configured in [`construct_runtime!`] as the `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", pallet_name_attribute)]
/// It requires that the given prefix type implements
/// [`PalletInfoAccess`](traits::PalletInfoAccess) (which is always the case for FRAME pallet
/// structs). In the example above, `Pallet<T>` is the prefix type.
///
/// 3. Use the `dynamic` prefix type. This prefix type calls [`Get::get()`](traits::Get::get)
/// to get the `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", dynamic_attribute)]
/// It requires that the given prefix type implements [`Get<'static str>`](traits::Get).
///
/// 4. Let the macro "guess" what kind of prefix type to use. This only supports verbatim or
/// pallet name. The macro uses the presence of generic arguments to the prefix type as an
/// indication that it should use the pallet name as the `prefix`:
#[doc = docify::embed!("src/tests/storage_alias.rs", storage_alias_guess)]
pub use frame_support_procedural::storage_alias;
pub use frame_support_procedural::derive_impl;
/// Experimental macros for defining dynamic params that can be used in pallet configs.
#[cfg(feature = "experimental")]
pub mod dynamic_params {
pub use frame_support_procedural::{
dynamic_aggregated_params_internal, dynamic_pallet_params, dynamic_params,
};
}
/// Create new implementations of the [`Get`](crate::traits::Get) trait.
///
/// The so-called parameter type can be created in four different ways:
///
/// - Using `const` to create a parameter type that provides a `const` getter. It is required that
/// the `value` is const.
///
/// - Declare the parameter type without `const` to have more freedom when creating the value.
///
/// - Using `storage` to create a storage parameter type. This type is special as it tries to load
/// the value from the storage under a fixed key. If the value could not be found in the storage,
/// the given default value will be returned. It is required that the value implements
/// [`Encode`](codec::Encode) and [`Decode`](codec::Decode). The key for looking up the value in
/// the storage is built using the following formula:
///
/// `twox_128(":" ++ NAME ++ ":")` where `NAME` is the name that is passed as type name.
///
/// - Using `static` to create a static parameter type. Its value is being provided by a static
/// variable with the equivalent name in `UPPER_SNAKE_CASE`. An additional `set` function is
/// provided in this case to alter the static variable. **This is intended for testing ONLY and is
/// ONLY available when `std` is enabled.**
///
/// # Examples
///
/// ```
/// # use frame_support::traits::Get;
/// # use frame_support::parameter_types;
/// // This function cannot be used in a const context.
/// fn non_const_expression() -> u64 { 99 }
///
/// const FIXED_VALUE: u64 = 10;
/// parameter_types! {
/// pub const Argument: u64 = 42 + FIXED_VALUE;
/// /// Visibility of the type is optional
/// OtherArgument: u64 = non_const_expression();
/// pub storage StorageArgument: u64 = 5;
/// pub static StaticArgument: u32 = 7;
/// }
///
/// trait Config {
/// type Parameter: Get<u64>;
/// type OtherParameter: Get<u64>;
/// type StorageParameter: Get<u64>;
/// type StaticParameter: Get<u32>;
/// }
///
/// struct Runtime;
/// impl Config for Runtime {
/// type Parameter = Argument;
/// type OtherParameter = OtherArgument;
/// type StorageParameter = StorageArgument;
/// type StaticParameter = StaticArgument;
/// }
///
/// // In testing, `StaticArgument` can be altered later: `StaticArgument::set(8)`.
/// ```
///
/// # Invalid example:
///
/// ```compile_fail
/// # use frame_support::traits::Get;
/// # use frame_support::parameter_types;
/// // This function cannot be used in a const context.
/// fn non_const_expression() -> u64 { 99 }
///
/// parameter_types! {
/// pub const Argument: u64 = non_const_expression();
/// }
/// ```
#[macro_export]
macro_rules! parameter_types {
(
$( #[ $attr:meta ] )*
$vis:vis const $name:ident $(< $($ty_params:ident),* >)?: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name $(
< $($ty_params),* >( $(core::marker::PhantomData<$ty_params>),* )
)?;
$crate::parameter_types!(IMPL_CONST $name , $type , $value $( $(, $ty_params)* )?);
$crate::parameter_types!( $( $rest )* );
);
(
$( #[ $attr:meta ] )*
$vis:vis $name:ident $(< $($ty_params:ident),* >)?: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name $(
< $($ty_params),* >( $(core::marker::PhantomData<$ty_params>),* )
)?;
$crate::parameter_types!(IMPL $name, $type, $value $( $(, $ty_params)* )?);
$crate::parameter_types!( $( $rest )* );
);
(
$( #[ $attr:meta ] )*
$vis:vis storage $name:ident $(< $($ty_params:ident),* >)?: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name $(
< $($ty_params),* >( $(core::marker::PhantomData<$ty_params>),* )
)?;
$crate::parameter_types!(IMPL_STORAGE $name, $type, $value $( $(, $ty_params)* )?);
$crate::parameter_types!( $( $rest )* );
);
() => ();
(IMPL_CONST $name:ident, $type:ty, $value:expr $(, $ty_params:ident)*) => {
impl< $($ty_params),* > $name< $($ty_params),* > {
/// Returns the value of this parameter type.
pub const fn get() -> $type {
$value
}
}
impl<_I: From<$type> $(, $ty_params)*> $crate::traits::Get<_I> for $name< $($ty_params),* > {
fn get() -> _I {
_I::from(Self::get())
}
}
impl< $($ty_params),* > $crate::traits::TypedGet for $name< $($ty_params),* > {
type Type = $type;
fn get() -> $type {
Self::get()
}
}
};
(IMPL $name:ident, $type:ty, $value:expr $(, $ty_params:ident)*) => {
impl< $($ty_params),* > $name< $($ty_params),* > {
/// Returns the value of this parameter type.
pub fn get() -> $type {
$value
}
}
impl<_I: From<$type>, $(, $ty_params)*> $crate::traits::Get<_I> for $name< $($ty_params),* > {
fn get() -> _I {
_I::from(Self::get())
}
}
impl< $($ty_params),* > $crate::traits::TypedGet for $name< $($ty_params),* > {
type Type = $type;
fn get() -> $type {
Self::get()
}
}
};
(IMPL_STORAGE $name:ident, $type:ty, $value:expr $(, $ty_params:ident)*) => {
#[allow(unused)]
impl< $($ty_params),* > $name< $($ty_params),* > {
/// Returns the key for this parameter type.
pub fn key() -> [u8; 16] {
$crate::__private::sp_crypto_hashing_proc_macro::twox_128!(b":", $name, b":")
}
/// Set the value of this parameter type in the storage.
///
/// This needs to be executed in an externalities provided environment.
pub fn set(value: &$type) {
$crate::storage::unhashed::put(&Self::key(), value);
}
/// Returns the value of this parameter type.
///
/// This needs to be executed in an externalities provided environment.
#[allow(unused)]
pub fn get() -> $type {
$crate::storage::unhashed::get(&Self::key()).unwrap_or_else(|| $value)
}
}
impl<_I: From<$type> $(, $ty_params)*> $crate::traits::Get<_I> for $name< $($ty_params),* > {
fn get() -> _I {
_I::from(Self::get())
}
}
impl< $($ty_params),* > $crate::traits::TypedGet for $name< $($ty_params),* > {
type Type = $type;
fn get() -> $type {
Self::get()
}
}
};
(
$( #[ $attr:meta ] )*
$vis:vis static $name:ident: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$crate::parameter_types_impl_thread_local!(
$( #[ $attr ] )*
$vis static $name: $type = $value;
);
$crate::parameter_types!( $( $rest )* );
);
}
#[cfg(not(feature = "std"))]
#[macro_export]
macro_rules! parameter_types_impl_thread_local {
( $( $any:tt )* ) => {
compile_error!("static parameter types is only available in std and for testing.");
};
}
#[cfg(feature = "std")]
#[macro_export]
macro_rules! parameter_types_impl_thread_local {
(
$(
$( #[ $attr:meta ] )*
$vis:vis static $name:ident: $type:ty = $value:expr;
)*
) => {
$crate::parameter_types_impl_thread_local!(
IMPL_THREAD_LOCAL $( $vis, $name, $type, $value, )*
);
$crate::__private::paste::item! {
$crate::parameter_types!(
$(
$( #[ $attr ] )*
$vis $name: $type = [<$name:snake:upper>].with(|v| v.borrow().clone());
)*
);
$(
impl $name {
/// Set the internal value.
pub fn set(t: $type) {
[<$name:snake:upper>].with(|v| *v.borrow_mut() = t);
}
/// Mutate the internal value in place.
#[allow(unused)]
pub fn mutate<R, F: FnOnce(&mut $type) -> R>(mutate: F) -> R{
let mut current = Self::get();
let result = mutate(&mut current);
Self::set(current);
result
}
/// Get current value and replace with initial value of the parameter type.
#[allow(unused)]
pub fn take() -> $type {
let current = Self::get();
Self::set($value);
current
}
}
)*
}
};
(IMPL_THREAD_LOCAL $( $vis:vis, $name:ident, $type:ty, $value:expr, )* ) => {
$crate::__private::paste::item! {
thread_local! {
$(
pub static [<$name:snake:upper>]: std::cell::RefCell<$type> =
std::cell::RefCell::new($value);
)*
}
}
};
}
/// Macro for easily creating a new implementation of both the `Get` and `Contains` traits. Use
/// exactly as with `parameter_types`, only the type must be `Ord`.
#[macro_export]
macro_rules! ord_parameter_types {
(
$( #[ $attr:meta ] )*
$vis:vis const $name:ident: $type:ty = $value:expr;
$( $rest:tt )*
) => (
$( #[ $attr ] )*
$vis struct $name;
$crate::parameter_types!{IMPL $name , $type , $value}
$crate::ord_parameter_types!{IMPL $name , $type , $value}
$crate::ord_parameter_types!{ $( $rest )* }
);
() => ();
(IMPL $name:ident , $type:ty , $value:expr) => {
impl $crate::traits::SortedMembers<$type> for $name {
fn contains(t: &$type) -> bool { &$value == t }
fn sorted_members() -> $crate::__private::Vec<$type> { vec![$value] }
fn count() -> usize { 1 }
#[cfg(feature = "runtime-benchmarks")]
fn add(_: &$type) {}
}
impl $crate::traits::Contains<$type> for $name {
fn contains(t: &$type) -> bool { &$value == t }
}
}
}
/// Print out a formatted message.
///
/// # Example
///
/// ```
/// frame_support::runtime_print!("my value is {}", 3);
/// ```
#[macro_export]
macro_rules! runtime_print {
($($arg:tt)+) => {
{
use core::fmt::Write;
let mut w = $crate::__private::sp_std::Writer::default();
let _ = core::write!(&mut w, $($arg)+);
$crate::__private::sp_io::misc::print_utf8(&w.inner())
}
}
}
/// Print out the debuggable type.
pub fn debug(data: &impl core::fmt::Debug) {
runtime_print!("{:?}", data);
}
#[doc(inline)]
pub use frame_support_procedural::{
construct_runtime, match_and_insert, transactional, PalletError, RuntimeDebugNoBound,
};
pub use frame_support_procedural::runtime;
#[doc(hidden)]
pub use frame_support_procedural::{__create_tt_macro, __generate_dummy_part_checker};
/// Derive [`Clone`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::CloneNoBound;
/// trait Config {
/// type C: Clone;
/// }
///
/// // Foo implements [`Clone`] because `C` bounds [`Clone`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Clone`].
/// #[derive(CloneNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::CloneNoBound;
/// Derive [`Eq`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::{EqNoBound, PartialEqNoBound};
/// trait Config {
/// type C: Eq;
/// }
///
/// // Foo implements [`Eq`] because `C` bounds [`Eq`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Eq`].
/// #[derive(PartialEqNoBound, EqNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::EqNoBound;
/// Derive [`PartialEq`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::PartialEqNoBound;
/// trait Config {
/// type C: PartialEq;
/// }
///
/// // Foo implements [`PartialEq`] because `C` bounds [`PartialEq`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`PartialEq`].
/// #[derive(PartialEqNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::PartialEqNoBound;
/// Derive [`Ord`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::{OrdNoBound, PartialOrdNoBound, EqNoBound, PartialEqNoBound};
/// trait Config {
/// type C: Ord;
/// }
///
/// // Foo implements [`Ord`] because `C` bounds [`Ord`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Ord`].
/// #[derive(EqNoBound, OrdNoBound, PartialEqNoBound, PartialOrdNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::OrdNoBound;
/// Derive [`PartialOrd`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::{OrdNoBound, PartialOrdNoBound, EqNoBound, PartialEqNoBound};
/// trait Config {
/// type C: PartialOrd;
/// }
///
/// // Foo implements [`PartialOrd`] because `C` bounds [`PartialOrd`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`PartialOrd`].
/// #[derive(PartialOrdNoBound, PartialEqNoBound, EqNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::PartialOrdNoBound;
/// Derive [`Debug`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::DebugNoBound;
/// # use core::fmt::Debug;
/// trait Config {
/// type C: Debug;
/// }
///
/// // Foo implements [`Debug`] because `C` bounds [`Debug`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Debug`].
/// #[derive(DebugNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
/// ```
pub use frame_support_procedural::DebugNoBound;
/// Derive [`Default`] but do not bound any generic.
///
/// This is useful for type generic over runtime:
/// ```
/// # use frame_support::DefaultNoBound;
/// # use core::default::Default;
/// trait Config {
/// type C: Default;
/// }
///
/// // Foo implements [`Default`] because `C` bounds [`Default`].
/// // Otherwise compilation will fail with an output telling `c` doesn't implement [`Default`].
/// #[derive(DefaultNoBound)]
/// struct Foo<T: Config> {
/// c: T::C,
/// }
///
/// // Also works with enums, by specifying the default with #[default]:
/// #[derive(DefaultNoBound)]
/// enum Bar<T: Config> {
/// // Bar will implement Default as long as all of the types within Baz also implement default.
/// #[default]
/// Baz(T::C),
/// Quxx,
/// }
/// ```
pub use frame_support_procedural::DefaultNoBound;
/// Assert the annotated function is executed within a storage transaction.
///
/// The assertion is enabled for native execution and when `debug_assertions` are enabled.
///
/// # Example
///
/// ```
/// # use frame_support::{
/// # require_transactional, transactional, dispatch::DispatchResult
/// # };
///
/// #[require_transactional]
/// fn update_all(value: u32) -> DispatchResult {
/// // Update multiple storages.
/// // Return `Err` to indicate should revert.
/// Ok(())
/// }
///
/// #[transactional]
/// fn safe_update(value: u32) -> DispatchResult {
/// // This is safe
/// update_all(value)
/// }
///
/// fn unsafe_update(value: u32) -> DispatchResult {
/// // this may panic if unsafe_update is not called within a storage transaction
/// update_all(value)
/// }
/// ```
pub use frame_support_procedural::require_transactional;
/// Convert the current crate version into a [`CrateVersion`](crate::traits::CrateVersion).
///
/// It uses the `CARGO_PKG_VERSION_MAJOR`, `CARGO_PKG_VERSION_MINOR` and
/// `CARGO_PKG_VERSION_PATCH` environment variables to fetch the crate version.
/// This means that the [`CrateVersion`](crate::traits::CrateVersion)
/// object will correspond to the version of the crate the macro is called in!
///
/// # Example
///
/// ```
/// # use frame_support::{traits::CrateVersion, crate_to_crate_version};
/// const Version: CrateVersion = crate_to_crate_version!();
/// ```
pub use frame_support_procedural::crate_to_crate_version;
/// Return Err of the expression: `return Err($expression);`.
///
/// Used as `fail!(expression)`.
#[macro_export]
macro_rules! fail {
( $y:expr ) => {{
return Err($y.into());
}};
}
/// Evaluate `$x:expr` and if not true return `Err($y:expr)`.
///
/// Used as `ensure!(expression_to_ensure, expression_to_return_on_false)`.
#[macro_export]
macro_rules! ensure {
( $x:expr, $y:expr $(,)? ) => {{
if !$x {
$crate::fail!($y);
}
}};
}
/// Evaluate an expression, assert it returns an expected `Err` value and that
/// runtime storage has not been mutated (i.e. expression is a no-operation).
///
/// Used as `assert_noop(expression_to_assert, expected_error_expression)`.
#[macro_export]
macro_rules! assert_noop {
(
$x:expr,
$y:expr $(,)?
) => {
let h = $crate::__private::storage_root($crate::__private::StateVersion::V1);
$crate::assert_err!($x, $y);
assert_eq!(
h,
$crate::__private::storage_root($crate::__private::StateVersion::V1),
"storage has been mutated"
);
};
}
/// Evaluate any expression and assert that runtime storage has not been mutated
/// (i.e. expression is a storage no-operation).
///
/// Used as `assert_storage_noop(expression_to_assert)`.
#[macro_export]
macro_rules! assert_storage_noop {
(
$x:expr
) => {
let h = $crate::__private::storage_root($crate::__private::StateVersion::V1);
$x;
assert_eq!(h, $crate::__private::storage_root($crate::__private::StateVersion::V1));
};
}
/// Assert an expression returns an error specified.
///
/// Used as `assert_err!(expression_to_assert, expected_error_expression)`
#[macro_export]
macro_rules! assert_err {
( $x:expr , $y:expr $(,)? ) => {
assert_eq!($x, Err($y.into()));
};
}
/// Assert an expression returns an error specified.
///
/// This can be used on `DispatchResultWithPostInfo` when the post info should
/// be ignored.
#[macro_export]
macro_rules! assert_err_ignore_postinfo {
( $x:expr , $y:expr $(,)? ) => {
$crate::assert_err!($x.map(|_| ()).map_err(|e| e.error), $y);
};
}
/// Assert an expression returns error with the given weight.
#[macro_export]
macro_rules! assert_err_with_weight {
($call:expr, $err:expr, $weight:expr $(,)? ) => {
if let Err(dispatch_err_with_post) = $call {
$crate::assert_err!($call.map(|_| ()).map_err(|e| e.error), $err);
assert_eq!(dispatch_err_with_post.post_info.actual_weight, $weight);
} else {
::core::panic!("expected Err(_), got Ok(_).")
}
};
}
/// Panic if an expression doesn't evaluate to `Ok`.
///
/// Used as `assert_ok!(expression_to_assert, expected_ok_expression)`,
/// or `assert_ok!(expression_to_assert)` which would assert against `Ok(())`.
#[macro_export]
macro_rules! assert_ok {
( $x:expr $(,)? ) => {
let is = $x;
match is {
Ok(_) => (),
_ => assert!(false, "Expected Ok(_). Got {:#?}", is),
}
};
( $x:expr, $y:expr $(,)? ) => {
assert_eq!($x, Ok($y));
};
}
/// Assert that the maximum encoding size does not exceed the value defined in
/// [`MAX_MODULE_ERROR_ENCODED_SIZE`] during compilation.
///
/// This macro is intended to be used in conjunction with `tt_call!`.
#[macro_export]
macro_rules! assert_error_encoded_size {
{
path = [{ $($path:ident)::+ }]
runtime = [{ $runtime:ident }]
assert_message = [{ $assert_message:literal }]
error = [{ $error:ident }]
} => {
const _: () = assert!(
<
$($path::)+$error<$runtime> as $crate::traits::PalletError
>::MAX_ENCODED_SIZE <= $crate::MAX_MODULE_ERROR_ENCODED_SIZE,
$assert_message
);
};
{
path = [{ $($path:ident)::+ }]
runtime = [{ $runtime:ident }]
assert_message = [{ $assert_message:literal }]
} => {};
}
/// Do something hypothetically by rolling back any changes afterwards.
///
/// Returns the original result of the closure.
#[macro_export]
#[cfg(feature = "experimental")]
macro_rules! hypothetically {
( $e:expr ) => {
$crate::storage::transactional::with_transaction(|| -> $crate::__private::TransactionOutcome<Result<_, $crate::__private::DispatchError>> {
$crate::__private::TransactionOutcome::Rollback(Ok($e))
},
).expect("Always returning Ok; qed")
};
}
/// Assert something to be *hypothetically* `Ok`, without actually committing it.
///
/// Reverts any storage changes made by the closure.
#[macro_export]
#[cfg(feature = "experimental")]
macro_rules! hypothetically_ok {
($e:expr $(, $args:expr)* $(,)?) => {
$crate::assert_ok!($crate::hypothetically!($e) $(, $args)*);
};
}
#[doc(hidden)]
pub use serde::{Deserialize, Serialize};
#[doc(hidden)]
pub use macro_magic;
/// Prelude to be used for pallet testing, for ease of use.
#[cfg(feature = "std")]
pub mod testing_prelude {
pub use super::{
assert_err, assert_err_ignore_postinfo, assert_err_with_weight, assert_error_encoded_size,
assert_noop, assert_ok, assert_storage_noop, parameter_types, traits::Get,
};
pub use sp_arithmetic::assert_eq_error_rate;
pub use sp_runtime::{bounded_btree_map, bounded_vec};
}
/// Prelude to be used alongside pallet macro, for ease of use.
pub mod pallet_prelude {
pub use crate::{
defensive, defensive_assert,
dispatch::{DispatchClass, DispatchResult, DispatchResultWithPostInfo, Parameter, Pays},
ensure,
inherent::{InherentData, InherentIdentifier, ProvideInherent},
storage,
storage::{
bounded_btree_map::BoundedBTreeMap,
bounded_btree_set::BoundedBTreeSet,
bounded_vec::BoundedVec,
types::{
CountedStorageMap, CountedStorageNMap, Key as NMapKey, OptionQuery, ResultQuery,
StorageDoubleMap, StorageMap, StorageNMap, StorageValue, ValueQuery,
},
weak_bounded_vec::WeakBoundedVec,
StorageList,
},
traits::{
BuildGenesisConfig, ConstU32, ConstUint, EnsureOrigin, Get, GetDefault,
GetStorageVersion, Hooks, IsType, PalletInfoAccess, StorageInfoTrait, StorageVersion,
Task, TypedGet,
},
Blake2_128, Blake2_128Concat, Blake2_256, CloneNoBound, DebugNoBound, EqNoBound, Identity,
PartialEqNoBound, RuntimeDebugNoBound, Twox128, Twox256, Twox64Concat,
};
pub use codec::{Decode, Encode, MaxEncodedLen};
pub use core::marker::PhantomData;
pub use frame_support::pallet_macros::*;
pub use frame_support_procedural::{inject_runtime_type, register_default_impl};
pub use scale_info::TypeInfo;
pub use sp_inherents::MakeFatalError;
pub use sp_runtime::{
traits::{
CheckedAdd, CheckedConversion, CheckedDiv, CheckedMul, CheckedShl, CheckedShr,
CheckedSub, MaybeSerializeDeserialize, Member, One, ValidateUnsigned, Zero,
},
transaction_validity::{
InvalidTransaction, TransactionLongevity, TransactionPriority, TransactionSource,
TransactionTag, TransactionValidity, TransactionValidityError, UnknownTransaction,
ValidTransaction,
},
DispatchError, RuntimeDebug, MAX_MODULE_ERROR_ENCODED_SIZE,
};
pub use sp_weights::Weight;
}
/// The pallet macro has 2 purposes:
///
/// * [For declaring a pallet as a rust module](#1---pallet-module-declaration)
/// * [For declaring the `struct` placeholder of a
/// pallet](#2---pallet-struct-placeholder-declaration)
///
/// # 1 - Pallet module declaration
///
/// The module to declare a pallet is organized as follows:
/// ```
/// #[frame_support::pallet] // <- the macro
/// mod pallet {
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {}
///
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// }
///
/// /* ... */
/// }
/// ```
///
/// The documentation for each individual part can be found at [frame_support::pallet_macros]
///
/// ## Dev Mode (`#[pallet(dev_mode)]`)
///
/// Syntax:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// /* ... */
/// }
/// ```
///
/// Specifying the argument `dev_mode` will allow you to enable dev mode for a pallet. The
/// aim of dev mode is to loosen some of the restrictions and requirements placed on
/// production pallets for easy tinkering and development. Dev mode pallets should not be
/// used in production. Enabling dev mode has the following effects:
///
/// * Weights no longer need to be specified on every `#[pallet::call]` declaration. By
/// default, dev mode pallets will assume a weight of zero (`0`) if a weight is not
/// specified. This is equivalent to specifying `#[weight(0)]` on all calls that do not
/// specify a weight.
/// * Call indices no longer need to be specified on every `#[pallet::call]` declaration. By
/// default, dev mode pallets will assume a call index based on the order of the call.
/// * All storages are marked as unbounded, meaning you do not need to implement
/// [`MaxEncodedLen`](frame_support::pallet_prelude::MaxEncodedLen) on storage types. This is
/// equivalent to specifying `#[pallet::unbounded]` on all storage type definitions.
/// * Storage hashers no longer need to be specified and can be replaced by `_`. In dev mode,
/// these will be replaced by `Blake2_128Concat`. In case of explicit key-binding, `Hasher`
/// can simply be ignored when in `dev_mode`.
///
/// Note that the `dev_mode` argument can only be supplied to the `#[pallet]` or
/// `#[frame_support::pallet]` attribute macro that encloses your pallet module. This
/// argument cannot be specified anywhere else, including but not limited to the
/// `#[pallet::pallet]` attribute macro.
///
/// <div class="example-wrap" style="display:inline-block"><pre class="compile_fail"
/// style="white-space:normal;font:inherit;">
/// <strong>WARNING</strong>:
/// You should never deploy or use dev mode pallets in production. Doing so can break your
/// chain. Once you are done tinkering, you should
/// remove the 'dev_mode' argument from your #[pallet] declaration and fix any compile
/// errors before attempting to use your pallet in a production scenario.
/// </pre></div>
///
/// # 2 - Pallet struct placeholder declaration
///
/// The pallet struct placeholder `#[pallet::pallet]` is mandatory and allows you to
/// specify pallet information.
///
/// The struct must be defined as follows:
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// #[pallet::pallet] // <- the macro
/// pub struct Pallet<T>(_); // <- the struct definition
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {}
/// }
/// ```
//
/// I.e. a regular struct definition named `Pallet`, with generic T and no where clause.
///
/// ## Macro expansion:
///
/// The macro adds this attribute to the Pallet struct definition:
/// ```ignore
/// #[derive(
/// frame_support::CloneNoBound,
/// frame_support::EqNoBound,
/// frame_support::PartialEqNoBound,
/// frame_support::RuntimeDebugNoBound,
/// )]
/// ```
/// and replaces the type `_` with `PhantomData<T>`.
///
/// It also implements on the pallet:
///
/// * [`GetStorageVersion`](frame_support::traits::GetStorageVersion)
/// * [`OnGenesis`](frame_support::traits::OnGenesis): contains some logic to write the pallet
/// version into storage.
/// * [`PalletInfoAccess`](frame_support::traits::PalletInfoAccess) to ease access to pallet
/// information given by [`frame_support::traits::PalletInfo`]. (The implementation uses the
/// associated type [`frame_support::traits::PalletInfo`]).
/// * [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) to give information about
/// storages.
///
/// If the attribute `set_storage_max_encoded_len` is set then the macro calls
/// [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) for each storage in the
/// implementation of [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) for the
/// pallet. Otherwise, it implements
/// [`StorageInfoTrait`](frame_support::traits::StorageInfoTrait) for the pallet using the
/// [`PartialStorageInfoTrait`](frame_support::traits::PartialStorageInfoTrait)
/// implementation of storages.
///
/// ## Note on deprecation.
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::pallet;
/// Contains macro stubs for all of the `pallet::` macros
pub mod pallet_macros {
/// Declare the storage as whitelisted from benchmarking.
///
/// Doing so will exclude reads of that value's storage key from counting towards weight
/// calculations during benchmarking.
///
/// This attribute should only be attached to storages that are known to be
/// read/used in every block. This will result in a more accurate benchmarking weight.
///
/// ### Example
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::whitelist_storage]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::whitelist_storage;
/// Allows specifying the weight of a call.
///
/// Each dispatchable needs to define a weight with the `#[pallet::weight($expr)]`
/// attribute. The first argument must be `origin: OriginFor<T>`.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// #[pallet::weight({0})] // <- set actual weight here
/// #[pallet::call_index(0)]
/// pub fn something(
/// _: OriginFor<T>,
/// foo: u32,
/// ) -> DispatchResult {
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::weight;
/// Allows whitelisting a storage item from decoding during try-runtime checks.
///
/// The optional attribute `#[pallet::disable_try_decode_storage]` will declare the
/// storage as whitelisted from decoding during try-runtime checks. This should only be
/// attached to transient storage which cannot be migrated during runtime upgrades.
///
/// ### Example
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::disable_try_decode_storage]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::disable_try_decode_storage;
/// Declares a storage as unbounded in potential size.
///
/// When implementing the storage info (when `#[pallet::generate_storage_info]` is
/// specified on the pallet struct placeholder), the size of the storage will be declared
/// as unbounded. This can be useful for storage which can never go into PoV (Proof of
/// Validity).
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::unbounded]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::unbounded;
/// Defines what storage prefix to use for a storage item when building the trie.
///
/// This is helpful if you wish to rename the storage field but don't want to perform a
/// migration.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::storage_prefix = "foo"]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
pub use frame_support_procedural::storage_prefix;
/// Ensures the generated `DefaultConfig` will not have any bounds for
/// that trait item.
///
/// Attaching this attribute to a trait item ensures that the generated trait
/// `DefaultConfig` will not have any bounds for this trait item.
///
/// As an example, if you have a trait item `type AccountId: SomeTrait;` in your `Config`
/// trait, the generated `DefaultConfig` will only have `type AccountId;` with no trait
/// bound.
pub use frame_support_procedural::no_default_bounds;
/// Ensures the trait item will not be used as a default with the
/// `#[derive_impl(..)]` attribute macro.
///
/// The optional attribute `#[pallet::no_default]` can be attached to trait items within a
/// `Config` trait impl that has [`#[pallet::config(with_default)]`](`config`)
/// attached.
pub use frame_support_procedural::no_default;
/// Declares a module as importable into a pallet via
/// [`#[import_section]`](`import_section`).
///
/// Note that sections are imported by their module name/ident, and should be referred to
/// by their _full path_ from the perspective of the target pallet. Do not attempt to make
/// use of `use` statements to bring pallet sections into scope, as this will not work
/// (unless you do so as part of a wildcard import, in which case it will work).
///
/// ## Naming Logistics
///
/// Also note that because of how `#[pallet_section]` works, pallet section names must be
/// globally unique _within the crate in which they are defined_. For more information on
/// why this must be the case, see macro_magic's
/// [`#[export_tokens]`](https://docs.rs/macro_magic/latest/macro_magic/attr.export_tokens.html) macro.
///
/// Optionally, you may provide an argument to `#[pallet_section]` such as
/// `#[pallet_section(some_ident)]`, in the event that there is another pallet section in
/// same crate with the same ident/name. The ident you specify can then be used instead of
/// the module's ident name when you go to import it via
/// [`#[import_section]`](`import_section`).
pub use frame_support_procedural::pallet_section;
/// The `#[pallet::inherent]` attribute allows the pallet to provide
/// [inherents](https://docs.substrate.io/fundamentals/transaction-types/#inherent-transactions).
///
/// An inherent is some piece of data that is inserted by a block authoring node at block
/// creation time and can either be accepted or rejected by validators based on whether the
/// data falls within an acceptable range.
///
/// The most common inherent is the `timestamp` that is inserted into every block. Since
/// there is no way to validate timestamps, validators simply check that the timestamp
/// reported by the block authoring node falls within an acceptable range.
///
/// Example usage:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_support::inherent::IsFatalError;
/// # use sp_timestamp::InherentError;
/// # use core::result;
/// #
/// // Example inherent identifier
/// pub const INHERENT_IDENTIFIER: InherentIdentifier = *b"timstap0";
///
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::inherent]
/// impl<T: Config> ProvideInherent for Pallet<T> {
/// type Call = Call<T>;
/// type Error = InherentError;
/// const INHERENT_IDENTIFIER: InherentIdentifier = INHERENT_IDENTIFIER;
///
/// fn create_inherent(data: &InherentData) -> Option<Self::Call> {
/// unimplemented!()
/// }
///
/// fn check_inherent(
/// call: &Self::Call,
/// data: &InherentData,
/// ) -> result::Result<(), Self::Error> {
/// unimplemented!()
/// }
///
/// fn is_inherent(call: &Self::Call) -> bool {
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// I.e. a trait implementation with bound `T: Config`, of trait `ProvideInherent` for type
/// `Pallet<T>`, and some optional where clause.
///
/// ## Macro expansion
///
/// The macro currently makes no use of this information, but it might use this information
/// in the future to give information directly to `construct_runtime`.
pub use frame_support_procedural::inherent;
/// Splits a pallet declaration into multiple parts.
///
/// An attribute macro that can be attached to a module declaration. Doing so will
/// import the contents of the specified external pallet section that is defined
/// elsewhere using [`#[pallet_section]`](`pallet_section`).
///
/// ## Example
/// ```
/// # use frame_support::pallet_macros::pallet_section;
/// # use frame_support::pallet_macros::import_section;
/// #
/// /// A [`pallet_section`] that defines the events for a pallet.
/// /// This can later be imported into the pallet using [`import_section`].
/// #[pallet_section]
/// mod events {
/// #[pallet::event]
/// #[pallet::generate_deposit(pub(super) fn deposit_event)]
/// pub enum Event<T: Config> {
/// /// Event documentation should end with an array that provides descriptive names for event
/// /// parameters. [something, who]
/// SomethingStored { something: u32, who: T::AccountId },
/// }
/// }
///
/// #[import_section(events)]
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {
/// # type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
/// # }
/// }
/// ```
///
/// This will result in the contents of `some_section` being _verbatim_ imported into
/// the pallet above. Note that since the tokens for `some_section` are essentially
/// copy-pasted into the target pallet, you cannot refer to imports that don't also
/// exist in the target pallet, but this is easily resolved by including all relevant
/// `use` statements within your pallet section, so they are imported as well, or by
/// otherwise ensuring that you have the same imports on the target pallet.
///
/// It is perfectly permissible to import multiple pallet sections into the same pallet,
/// which can be done by having multiple `#[import_section(something)]` attributes
/// attached to the pallet.
///
/// Note that sections are imported by their module name/ident, and should be referred to
/// by their _full path_ from the perspective of the target pallet.
pub use frame_support_procedural::import_section;
/// Allows defining getter functions on `Pallet` storage.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// #[pallet::getter(fn my_getter_fn_name)]
/// pub type MyStorage<T> = StorageValue<_, u32>;
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// See [`pallet::storage`](`frame_support::pallet_macros::storage`) for more info.
pub use frame_support_procedural::getter;
/// Defines constants that are added to the constant field of
/// [`PalletMetadata`](frame_metadata::v15::PalletMetadata) struct for this pallet.
///
/// Must be defined like:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// #
/// #[pallet::extra_constants]
/// impl<T: Config> Pallet<T> // $optional_where_clause
/// {
/// #[pallet::constant_name(SomeU32ConstantName)]
/// /// Some doc
/// fn some_u32_constant() -> u32 {
/// 100u32
/// }
/// }
/// }
/// ```
///
/// I.e. a regular rust `impl` block with some optional where clause and functions with 0
/// args, 0 generics, and some return type.
pub use frame_support_procedural::extra_constants;
#[rustfmt::skip]
/// Allows bypassing the `frame_system::Config` supertrait check.
///
/// To bypass the syntactic `frame_system::Config` supertrait check, use the attribute
/// `pallet::disable_frame_system_supertrait_check`.
///
/// Note this bypass is purely syntactic, and does not actually remove the requirement that your
/// pallet implements `frame_system::Config`. When using this check, your config is still required to implement
/// `frame_system::Config` either via
/// - Implementing a trait that itself implements `frame_system::Config`
/// - Tightly coupling it with another pallet which itself implements `frame_system::Config`
///
/// e.g.
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// trait OtherTrait: frame_system::Config {}
///
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config]
/// #[pallet::disable_frame_system_supertrait_check]
/// pub trait Config: OtherTrait {}
/// }
/// ```
///
/// To learn more about supertraits, see the
/// [trait_based_programming](../../polkadot_sdk_docs/reference_docs/trait_based_programming/index.html)
/// reference doc.
pub use frame_support_procedural::disable_frame_system_supertrait_check;
/// The mandatory attribute allowing definition of configurable types for the pallet.
///
/// Item must be defined as:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config // + $optionally_some_other_supertraits
/// // $optional_where_clause
/// {
/// // config items here
/// }
/// }
/// ```
///
/// I.e. a regular trait definition named `Config`, with the supertrait
/// [`frame_system::pallet::Config`](../../frame_system/pallet/trait.Config.html), and
/// optionally other supertraits and a where clause. (Specifying other supertraits here is
/// known as [tight coupling](https://docs.substrate.io/reference/how-to-guides/pallet-design/use-tight-coupling/))
///
/// The associated type `RuntimeEvent` is reserved. If defined, it must have the bounds
/// `From<Event>` and `IsType<<Self as frame_system::Config>::RuntimeEvent>`.
///
/// [`#[pallet::event]`](`event`) must be present if `RuntimeEvent`
/// exists as a config item in your `#[pallet::config]`.
///
/// ## Optional: `with_default`
///
/// An optional `with_default` argument may also be specified. Doing so will automatically
/// generate a `DefaultConfig` trait inside your pallet which is suitable for use with
/// [`#[derive_impl(..)`](`frame_support::derive_impl`) to derive a default testing
/// config:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// # use core::fmt::Debug;
/// # use frame_support::traits::Contains;
/// #
/// # pub trait SomeMoreComplexBound {}
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config(with_default)] // <- with_default is optional
/// pub trait Config: frame_system::Config {
/// /// The overarching event type.
/// #[pallet::no_default_bounds] // Default with bounds is not supported for RuntimeEvent
/// type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
///
/// /// A more complex type.
/// #[pallet::no_default] // Example of type where no default should be provided
/// type MoreComplexType: SomeMoreComplexBound;
///
/// /// A simple type.
/// // Default with bounds is supported for simple types
/// type SimpleType: From<u32>;
/// }
///
/// #[pallet::event]
/// pub enum Event<T: Config> {
/// SomeEvent(u16, u32),
/// }
/// }
/// ```
///
/// As shown above:
/// * you may attach the [`#[pallet::no_default]`](`no_default`)
/// attribute to specify that a particular trait item _cannot_ be used as a default when a
/// test `Config` is derived using the [`#[derive_impl(..)]`](`frame_support::derive_impl`)
/// attribute macro. This will cause that particular trait item to simply not appear in
/// default testing configs based on this config (the trait item will not be included in
/// `DefaultConfig`).
/// * you may attach the [`#[pallet::no_default_bounds]`](`no_default_bounds`)
/// attribute to specify that a particular trait item can be used as a default when a
/// test `Config` is derived using the [`#[derive_impl(..)]`](`frame_support::derive_impl`)
/// attribute macro. But its bounds cannot be enforced at this point and should be
/// discarded when generating the default config trait.
/// * you may not specify any attribute to generate a trait item in the default config
/// trait.
///
/// In case origin of error is not clear it is recommended to disable all default with
/// [`#[pallet::no_default]`](`no_default`) and enable them one by one.
///
/// ### `DefaultConfig` Caveats
///
/// The auto-generated `DefaultConfig` trait:
/// - is always a _subset_ of your pallet's `Config` trait.
/// - can only contain items that don't rely on externalities, such as
/// `frame_system::Config`.
///
/// Trait items that _do_ rely on externalities should be marked with
/// [`#[pallet::no_default]`](`no_default`)
///
/// Consequently:
/// - Any items that rely on externalities _must_ be marked with
/// [`#[pallet::no_default]`](`no_default`) or your trait will fail to compile when used
/// with [`derive_impl`](`frame_support::derive_impl`).
/// - Items marked with [`#[pallet::no_default]`](`no_default`) are entirely excluded from
/// the `DefaultConfig` trait, and therefore any impl of `DefaultConfig` doesn't need to
/// implement such items.
///
/// For more information, see:
/// * [`frame_support::derive_impl`].
/// * [`#[pallet::no_default]`](`no_default`)
/// * [`#[pallet::no_default_bounds]`](`no_default_bounds`)
///
/// ## Optional: `without_automatic_metadata`
///
/// By default, the associated types of the `Config` trait that require the `TypeInfo` or
/// `Parameter` bounds are included in the metadata of the pallet.
///
/// The optional `without_automatic_metadata` argument can be used to exclude these
/// associated types from the metadata collection.
///
/// Furthermore, the `without_automatic_metadata` argument can be used in combination with
/// the [`#[pallet::include_metadata]`](`include_metadata`) attribute to selectively
/// include only certain associated types in the metadata collection.
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// # use core::fmt::Debug;
/// # use frame_support::traits::Contains;
/// #
/// # pub trait SomeMoreComplexBound {}
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::config(with_default, without_automatic_metadata)] // <- with_default and without_automatic_metadata are optional
/// pub trait Config: frame_system::Config {
/// /// The overarching event type.
/// #[pallet::no_default_bounds] // Default with bounds is not supported for RuntimeEvent
/// type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
///
/// /// A simple type.
/// // Type that would have been included in metadata, but is now excluded.
/// type SimpleType: From<u32> + TypeInfo;
///
/// // The `pallet::include_metadata` is used to selectively include this type in metadata.
/// #[pallet::include_metadata]
/// type SelectivelyInclude: From<u32> + TypeInfo;
/// }
///
/// #[pallet::event]
/// pub enum Event<T: Config> {
/// SomeEvent(u16, u32),
/// }
/// }
/// ```
pub use frame_support_procedural::config;
/// Allows defining an enum that gets composed as an aggregate enum by `construct_runtime`.
///
/// The `#[pallet::composite_enum]` attribute allows you to define an enum that gets
/// composed as an aggregate enum by `construct_runtime`. This is similar in principle with
/// [frame_support_procedural::event] and [frame_support_procedural::error].
///
/// The attribute currently only supports enum definitions, and identifiers that are named
/// `FreezeReason`, `HoldReason`, `LockId` or `SlashReason`. Arbitrary identifiers for the
/// enum are not supported. The aggregate enum generated by
/// [`frame_support::construct_runtime`] will have the name of `RuntimeFreezeReason`,
/// `RuntimeHoldReason`, `RuntimeLockId` and `RuntimeSlashReason` respectively.
///
/// NOTE: The aggregate enum generated by `construct_runtime` generates a conversion
/// function from the pallet enum to the aggregate enum, and automatically derives the
/// following traits:
///
/// ```ignore
/// Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, MaxEncodedLen, TypeInfo,
/// RuntimeDebug
/// ```
///
/// For ease of usage, when no `#[derive]` attributes are found for the enum under
/// [`#[pallet::composite_enum]`](composite_enum), the aforementioned traits are
/// automatically derived for it. The inverse is also true: if there are any `#[derive]`
/// attributes found for the enum, then no traits will automatically be derived for it.
///
/// e.g, defining `HoldReason` in a pallet
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::composite_enum]
/// pub enum HoldReason {
/// /// The NIS Pallet has reserved it for a non-fungible receipt.
/// #[codec(index = 0)]
/// SomeHoldReason,
/// #[codec(index = 1)]
/// SomeOtherHoldReason,
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
pub use frame_support_procedural::composite_enum;
/// Allows the pallet to validate unsigned transactions.
///
/// Item must be defined as:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::validate_unsigned]
/// impl<T: Config> sp_runtime::traits::ValidateUnsigned for Pallet<T> {
/// type Call = Call<T>;
///
/// fn validate_unsigned(_source: TransactionSource, _call: &Self::Call) -> TransactionValidity {
/// // Your implementation details here
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// I.e. a trait implementation with bound `T: Config`, of trait
/// [`ValidateUnsigned`](frame_support::pallet_prelude::ValidateUnsigned) for
/// type `Pallet<T>`, and some optional where clause.
///
/// NOTE: There is also the [`sp_runtime::traits::TransactionExtension`] trait that can be
/// used to add some specific logic for transaction validation.
///
/// ## Macro expansion
///
/// The macro currently makes no use of this information, but it might use this information
/// in the future to give information directly to [`frame_support::construct_runtime`].
pub use frame_support_procedural::validate_unsigned;
/// Allows defining a struct implementing the [`Get`](frame_support::traits::Get) trait to
/// ease the use of storage types.
///
/// This attribute is meant to be used alongside [`#[pallet::storage]`](`storage`) to
/// define a storage's default value. This attribute can be used multiple times.
///
/// Item must be defined as:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use sp_runtime::FixedU128;
/// # use frame_support::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::storage]
/// pub(super) type SomeStorage<T: Config> =
/// StorageValue<_, FixedU128, ValueQuery, DefaultForSomeValue>;
///
/// // Define default for ParachainId
/// #[pallet::type_value]
/// pub fn DefaultForSomeValue() -> FixedU128 {
/// FixedU128::from_u32(1)
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// ## Macro expansion
///
/// The macro renames the function to some internal name, generates a struct with the
/// original name of the function and its generic, and implements `Get<$ReturnType>` by
/// calling the user defined function.
pub use frame_support_procedural::type_value;
/// Allows defining a storage version for the pallet.
///
/// Because the `pallet::pallet` macro implements
/// [`GetStorageVersion`](frame_support::traits::GetStorageVersion), the current storage
/// version needs to be communicated to the macro. This can be done by using the
/// `pallet::storage_version` attribute:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::StorageVersion;
/// # use frame_support::traits::GetStorageVersion;
/// #
/// const STORAGE_VERSION: StorageVersion = StorageVersion::new(5);
///
/// #[pallet::pallet]
/// #[pallet::storage_version(STORAGE_VERSION)]
/// pub struct Pallet<T>(_);
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// If not present, the current storage version is set to the default value.
pub use frame_support_procedural::storage_version;
/// The `#[pallet::hooks]` attribute allows you to specify a
/// [`frame_support::traits::Hooks`] implementation for `Pallet` that specifies
/// pallet-specific logic.
///
/// The item the attribute attaches to must be defined as follows:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::hooks]
/// impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {
/// // Implement hooks here
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
/// I.e. a regular trait implementation with generic bound: `T: Config`, for the trait
/// `Hooks<BlockNumberFor<T>>` (they are defined in preludes), for the type `Pallet<T>`.
///
/// Optionally, you could add a where clause.
///
/// ## Macro expansion
///
/// The macro implements the traits
/// [`OnInitialize`](frame_support::traits::OnInitialize),
/// [`OnIdle`](frame_support::traits::OnIdle),
/// [`OnFinalize`](frame_support::traits::OnFinalize),
/// [`OnRuntimeUpgrade`](frame_support::traits::OnRuntimeUpgrade),
/// [`OffchainWorker`](frame_support::traits::OffchainWorker), and
/// [`IntegrityTest`](frame_support::traits::IntegrityTest) using
/// the provided [`Hooks`](frame_support::traits::Hooks) implementation.
///
/// NOTE: `OnRuntimeUpgrade` is implemented with `Hooks::on_runtime_upgrade` and some
/// additional logic. E.g. logic to write the pallet version into storage.
///
/// NOTE: The macro also adds some tracing logic when implementing the above traits. The
/// following hooks emit traces: `on_initialize`, `on_finalize` and `on_runtime_upgrade`.
pub use frame_support_procedural::hooks;
/// Generates a helper function on `Pallet` that handles deposit events.
///
/// NOTE: For instantiable pallets, the event must be generic over `T` and `I`.
///
/// ## Macro expansion
///
/// The macro will add on enum `Event` the attributes:
/// * `#[derive(`[`frame_support::CloneNoBound`]`)]`
/// * `#[derive(`[`frame_support::EqNoBound`]`)]`
/// * `#[derive(`[`frame_support::PartialEqNoBound`]`)]`
/// * `#[derive(`[`frame_support::RuntimeDebugNoBound`]`)]`
/// * `#[derive(`[`codec::Encode`]`)]`
/// * `#[derive(`[`codec::Decode`]`)]`
///
/// The macro implements `From<Event<..>>` for ().
///
/// The macro implements a metadata function on `Event` returning the `EventMetadata`.
///
/// If `#[pallet::generate_deposit]` is present then the macro implements `fn
/// deposit_event` on `Pallet`.
pub use frame_support_procedural::generate_deposit;
/// Allows defining logic to make an extrinsic call feeless.
///
/// Each dispatchable may be annotated with the `#[pallet::feeless_if($closure)]`
/// attribute, which explicitly defines the condition for the dispatchable to be feeless.
///
/// The arguments for the closure must be the referenced arguments of the dispatchable
/// function.
///
/// The closure must return `bool`.
///
/// ### Example
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// #[pallet::call_index(0)]
/// /// Marks this call as feeless if `foo` is zero.
/// #[pallet::feeless_if(|_origin: &OriginFor<T>, foo: &u32| -> bool {
/// *foo == 0
/// })]
/// pub fn something(
/// _: OriginFor<T>,
/// foo: u32,
/// ) -> DispatchResult {
/// unimplemented!()
/// }
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// Please note that this only works for signed dispatchables and requires a transaction
/// extension such as [`pallet_skip_feeless_payment::SkipCheckIfFeeless`] to wrap the
/// existing payment extension. Else, this is completely ignored and the dispatchable is
/// still charged.
///
/// Also this will not allow accountless caller to send a transaction if some transaction
/// extension such as `frame_system::CheckNonce` is used.
/// Extensions such as `frame_system::CheckNonce` require a funded account to validate
/// the transaction.
///
/// ### Macro expansion
///
/// The macro implements the [`pallet_skip_feeless_payment::CheckIfFeeless`] trait on the
/// dispatchable and calls the corresponding closure in the implementation.
///
/// [`pallet_skip_feeless_payment::SkipCheckIfFeeless`]: ../../pallet_skip_feeless_payment/struct.SkipCheckIfFeeless.html
/// [`pallet_skip_feeless_payment::CheckIfFeeless`]: ../../pallet_skip_feeless_payment/struct.SkipCheckIfFeeless.html
pub use frame_support_procedural::feeless_if;
/// Allows defining an error enum that will be returned from the dispatchable when an error
/// occurs.
///
/// The information for this error type is then stored in runtime metadata.
///
/// Item must be defined as so:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::error]
/// pub enum Error<T> {
/// /// SomeFieldLessVariant doc
/// SomeFieldLessVariant,
/// /// SomeVariantWithOneField doc
/// SomeVariantWithOneField(u32),
/// }
/// #
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// }
/// ```
/// I.e. a regular enum named `Error`, with generic `T` and fieldless or multiple-field
/// variants.
///
/// Any field type in the enum variants must implement [`scale_info::TypeInfo`] in order to
/// be properly used in the metadata, and its encoded size should be as small as possible,
/// preferably 1 byte in size in order to reduce storage size. The error enum itself has an
/// absolute maximum encoded size specified by
/// [`frame_support::MAX_MODULE_ERROR_ENCODED_SIZE`].
///
/// (1 byte can still be 256 different errors. The more specific the error, the easier it
/// is to diagnose problems and give a better experience to the user. Don't skimp on having
/// lots of individual error conditions.)
///
/// Field types in enum variants must also implement [`frame_support::PalletError`],
/// otherwise the pallet will fail to compile. Rust primitive types have already
/// implemented the [`frame_support::PalletError`] trait along with some commonly used
/// stdlib types such as [`Option`] and [`core::marker::PhantomData`], and hence
/// in most use cases, a manual implementation is not necessary and is discouraged.
///
/// The generic `T` must not bound anything and a `where` clause is not allowed. That said,
/// bounds and/or a where clause should not needed for any use-case.
///
/// ## Macro expansion
///
/// The macro implements the [`Debug`] trait and functions `as_u8` using variant position,
/// and `as_str` using variant doc.
///
/// The macro also implements `From<Error<T>>` for `&'static str` and `From<Error<T>>` for
/// `DispatchError`.
///
/// ## Note on deprecation of Errors
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
/// - It's possible to deprecated either certain variants inside the `Error` or the whole
/// `Error` itself. If both the `Error` and its variants are deprecated a compile error
/// will be returned.
pub use frame_support_procedural::error;
/// Allows defining pallet events.
///
/// Pallet events are stored under the `system` / `events` key when the block is applied
/// (and then replaced when the next block writes it's events).
///
/// The Event enum can be defined as follows:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// # use frame_support::pallet_prelude::IsType;
/// #
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::event]
/// #[pallet::generate_deposit(fn deposit_event)] // Optional
/// pub enum Event<T> {
/// /// SomeEvent doc
/// SomeEvent(u16, u32), // SomeEvent with two fields
/// }
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {
/// /// The overarching runtime event type.
/// type RuntimeEvent: From<Event<Self>>
/// + IsType<<Self as frame_system::Config>::RuntimeEvent>;
/// }
/// }
/// ```
///
/// I.e. an enum (with named or unnamed fields variant), named `Event`, with generic: none
/// or `T` or `T: Config`, and optional w here clause.
///
/// `RuntimeEvent` must be defined in the `Config`, as shown in the example.
///
/// Each field must implement [`Clone`], [`Eq`], [`PartialEq`], [`codec::Encode`],
/// [`codec::Decode`], and [`Debug`] (on std only). For ease of use, bound by the trait
/// `Member`, available in [`frame_support::pallet_prelude`].
///
/// ## Note on deprecation of Events
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
/// - It's possible to deprecated either certain variants inside the `Event` or the whole
/// `Event` itself. If both the `Event` and its variants are deprecated a compile error
/// will be returned.
pub use frame_support_procedural::event;
/// Selectively includes associated types in the metadata.
///
/// The optional attribute allows you to selectively include associated types in the
/// metadata. This can be attached to trait items that implement `TypeInfo`.
///
/// By default all collectable associated types are included in the metadata.
///
/// This attribute can be used in combination with the
/// [`#[pallet::config(without_automatic_metadata)]`](`config`).
pub use frame_support_procedural::include_metadata;
/// Allows a pallet to declare a set of functions as a *dispatchable extrinsic*.
///
/// In slightly simplified terms, this macro declares the set of "transactions" of a
/// pallet.
///
/// > The exact definition of **extrinsic** can be found in
/// > [`sp_runtime::generic::UncheckedExtrinsic`].
///
/// A **dispatchable** is a common term in FRAME, referring to process of constructing a
/// function, and dispatching it with the correct inputs. This is commonly used with
/// extrinsics, for example "an extrinsic has been dispatched". See
/// [`sp_runtime::traits::Dispatchable`] and [`crate::traits::UnfilteredDispatchable`].
///
/// ## Call Enum
///
/// The macro is called `call` (rather than `#[pallet::extrinsics]`) because of the
/// generation of a `enum Call`. This enum contains only the encoding of the function
/// arguments of the dispatchable, alongside the information needed to route it to the
/// correct function.
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// pub mod custom_pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::BuildGenesisConfig;
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// pub fn some_dispatchable(_origin: OriginFor<T>, _input: u32) -> DispatchResult {
/// Ok(())
/// }
/// pub fn other(_origin: OriginFor<T>, _input: u64) -> DispatchResult {
/// Ok(())
/// }
/// }
///
/// // generates something like:
/// // enum Call<T: Config> {
/// // some_dispatchable { input: u32 }
/// // other { input: u64 }
/// // }
/// }
///
/// fn main() {
/// # use frame_support::{derive_impl, construct_runtime};
/// # use frame_support::__private::codec::Encode;
/// # use frame_support::__private::TestExternalities;
/// # use frame_support::traits::UnfilteredDispatchable;
/// # impl custom_pallet::Config for Runtime {}
/// # #[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
/// # impl frame_system::Config for Runtime {
/// # type Block = frame_system::mocking::MockBlock<Self>;
/// # }
/// construct_runtime! {
/// pub enum Runtime {
/// System: frame_system,
/// Custom: custom_pallet
/// }
/// }
///
/// # TestExternalities::new_empty().execute_with(|| {
/// let origin: RuntimeOrigin = frame_system::RawOrigin::Signed(10).into();
/// // calling into a dispatchable from within the runtime is simply a function call.
/// let _ = custom_pallet::Pallet::<Runtime>::some_dispatchable(origin.clone(), 10);
///
/// // calling into a dispatchable from the outer world involves constructing the bytes of
/// let call = custom_pallet::Call::<Runtime>::some_dispatchable { input: 10 };
/// let _ = call.clone().dispatch_bypass_filter(origin);
///
/// // the routing of a dispatchable is simply done through encoding of the `Call` enum,
/// // which is the index of the variant, followed by the arguments.
/// assert_eq!(call.encode(), vec![0u8, 10, 0, 0, 0]);
///
/// // notice how in the encoding of the second function, the first byte is different and
/// // referring to the second variant of `enum Call`.
/// let call = custom_pallet::Call::<Runtime>::other { input: 10 };
/// assert_eq!(call.encode(), vec![1u8, 10, 0, 0, 0, 0, 0, 0, 0]);
/// # });
/// }
/// ```
///
/// Further properties of dispatchable functions are as follows:
///
/// - Unless if annotated by `dev_mode`, it must contain [`weight`] to denote the
/// pre-dispatch weight consumed.
/// - The dispatchable must declare its index via [`call_index`], which can override the
/// position of a function in `enum Call`.
/// - The first argument is always an `OriginFor` (or `T::RuntimeOrigin`).
/// - The return type is always [`crate::dispatch::DispatchResult`] (or
/// [`crate::dispatch::DispatchResultWithPostInfo`]).
///
/// **WARNING**: modifying dispatchables, changing their order (i.e. using [`call_index`]),
/// removing some, etc., must be done with care. This will change the encoding of the , and
/// the call can be stored on-chain (e.g. in `pallet-scheduler`). Thus, migration might be
/// needed. This is why the use of `call_index` is mandatory by default in FRAME.
///
/// ## Default Behavior
///
/// If no `#[pallet::call]` exists, then a default implementation corresponding to the
/// following code is automatically generated:
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// mod pallet {
/// #[pallet::pallet]
/// pub struct Pallet<T>(_);
///
/// #[pallet::call] // <- automatically generated
/// impl<T: Config> Pallet<T> {} // <- automatically generated
///
/// #[pallet::config]
/// pub trait Config: frame_system::Config {}
/// }
/// ```
///
/// ## Note on deprecation of Calls
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::call;
/// Enforce the index of a variant in the generated `enum Call`.
///
/// See [`call`] for more information.
///
/// All call indexes start from 0, until it encounters a dispatchable function with a
/// defined call index. The dispatchable function that lexically follows the function with
/// a defined call index will have that call index, but incremented by 1, e.g. if there are
/// 3 dispatchable functions `fn foo`, `fn bar` and `fn qux` in that order, and only `fn
/// bar` has a call index of 10, then `fn qux` will have an index of 11, instead of 1.
pub use frame_support_procedural::call_index;
/// Declares the arguments of a [`call`] function to be encoded using
/// [`codec::Compact`].
///
/// This will results in smaller extrinsic encoding.
///
/// A common example of `compact` is for numeric values that are often times far far away
/// from their theoretical maximum. For example, in the context of a crypto-currency, the
/// balance of an individual account is oftentimes way less than what the numeric type
/// allows. In all such cases, using `compact` is sensible.
///
/// ```
/// #[frame_support::pallet(dev_mode)]
/// pub mod custom_pallet {
/// # use frame_support::pallet_prelude::*;
/// # use frame_system::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::BuildGenesisConfig;
/// #[pallet::call]
/// impl<T: Config> Pallet<T> {
/// pub fn some_dispatchable(_origin: OriginFor<T>, #[pallet::compact] _input: u32) -> DispatchResult {
/// Ok(())
/// }
/// }
/// }
pub use frame_support_procedural::compact;
/// Allows you to define the genesis configuration for the pallet.
///
/// Item is defined as either an enum or a struct. It needs to be public and implement the
/// trait [`frame_support::traits::BuildGenesisConfig`].
///
/// See [`genesis_build`] for an example.
pub use frame_support_procedural::genesis_config;
/// Allows you to define how the state of your pallet at genesis is built. This
/// takes as input the `GenesisConfig` type (as `self`) and constructs the pallet's initial
/// state.
///
/// The fields of the `GenesisConfig` can in turn be populated by the chain-spec.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// pub mod pallet {
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::BuildGenesisConfig;
/// #[pallet::genesis_config]
/// #[derive(frame_support::DefaultNoBound)]
/// pub struct GenesisConfig<T: Config> {
/// foo: Vec<T::AccountId>
/// }
///
/// #[pallet::genesis_build]
/// impl<T: Config> BuildGenesisConfig for GenesisConfig<T> {
/// fn build(&self) {
/// // use &self to access fields.
/// let foo = &self.foo;
/// todo!()
/// }
/// }
/// }
/// ```
///
/// ## Former Usage
///
/// Prior to <https://github.com/paritytech/substrate/pull/14306>, the following syntax was used.
/// This is deprecated and will soon be removed.
///
/// ```
/// #[frame_support::pallet]
/// pub mod pallet {
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// # use frame_support::traits::GenesisBuild;
/// #[pallet::genesis_config]
/// #[derive(frame_support::DefaultNoBound)]
/// pub struct GenesisConfig<T: Config> {
/// foo: Vec<T::AccountId>
/// }
///
/// #[pallet::genesis_build]
/// impl<T: Config> GenesisBuild<T> for GenesisConfig<T> {
/// fn build(&self) {
/// todo!()
/// }
/// }
/// }
/// ```
pub use frame_support_procedural::genesis_build;
/// Allows adding an associated type trait bounded by
/// [`Get`](frame_support::pallet_prelude::Get) from [`pallet::config`](`macro@config`)
/// into metadata.
///
/// ## Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// use frame_support::pallet_prelude::*;
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// #[pallet::config]
/// pub trait Config: frame_system::Config {
/// /// This is like a normal `Get` trait, but it will be added into metadata.
/// #[pallet::constant]
/// type Foo: Get<u32>;
/// }
/// }
/// ```
///
/// ## Note on deprecation of constants
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::constant;
/// Declares a type alias as a storage item.
///
/// Storage items are pointers to data stored on-chain (the *blockchain state*), under a
/// specific key. The exact key is dependent on the type of the storage.
///
/// > From the perspective of this pallet, the entire blockchain state is abstracted behind
/// > a key-value api, namely [`sp_io::storage`].
///
/// ## Storage Types
///
/// The following storage types are supported by the `#[storage]` macro. For specific
/// information about each storage type, refer to the documentation of the respective type.
///
/// * [`StorageValue`](crate::storage::types::StorageValue)
/// * [`StorageMap`](crate::storage::types::StorageMap)
/// * [`CountedStorageMap`](crate::storage::types::CountedStorageMap)
/// * [`StorageDoubleMap`](crate::storage::types::StorageDoubleMap)
/// * [`StorageNMap`](crate::storage::types::StorageNMap)
/// * [`CountedStorageNMap`](crate::storage::types::CountedStorageNMap)
///
/// ## Storage Type Usage
///
/// The following details are relevant to all of the aforementioned storage types.
/// Depending on the exact storage type, it may require the following generic parameters:
///
/// * [`Prefix`](#prefixes) - Used to give the storage item a unique key in the underlying
/// storage.
/// * `Key` - Type of the keys used to store the values,
/// * `Value` - Type of the value being stored,
/// * [`Hasher`](#hashers) - Used to ensure the keys of a map are uniformly distributed,
/// * [`QueryKind`](#querykind) - Used to configure how to handle queries to the underlying
/// storage,
/// * `OnEmpty` - Used to handle missing values when querying the underlying storage,
/// * `MaxValues` - _not currently used_.
///
/// Each `Key` type requires its own designated `Hasher` declaration, so that
/// [`StorageDoubleMap`](frame_support::storage::types::StorageDoubleMap) needs two of
/// each, and [`StorageNMap`](frame_support::storage::types::StorageNMap) needs `N` such
/// pairs. Since [`StorageValue`](frame_support::storage::types::StorageValue) only stores
/// a single element, no configuration of hashers is needed.
///
/// ### Syntax
///
/// Two general syntaxes are supported, as demonstrated below:
///
/// 1. Named type parameters, e.g., `type Foo<T> = StorageValue<Value = u32>`.
/// 2. Positional type parameters, e.g., `type Foo<T> = StorageValue<_, u32>`.
///
/// In both instances, declaring the generic parameter `<T>` is mandatory. Optionally, it
/// can also be explicitly declared as `<T: Config>`. In the compiled code, `T` will
/// automatically include the trait bound `Config`.
///
/// Note that in positional syntax, the first generic type parameter must be `_`.
///
/// #### Example
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// /// Positional syntax, without bounding `T`.
/// #[pallet::storage]
/// pub type Foo<T> = StorageValue<_, u32>;
///
/// /// Positional syntax, with bounding `T`.
/// #[pallet::storage]
/// pub type Bar<T: Config> = StorageValue<_, u32>;
///
/// /// Named syntax.
/// #[pallet::storage]
/// pub type Baz<T> = StorageMap<Hasher = Blake2_128Concat, Key = u32, Value = u32>;
/// }
/// ```
///
/// ### Value Trait Bounds
///
/// To use a type as the value of a storage type, be it `StorageValue`, `StorageMap` or
/// anything else, you need to meet a number of trait bound constraints.
///
/// See: <https://paritytech.github.io/polkadot-sdk/master/polkadot_sdk_docs/reference_docs/frame_storage_derives/index.html>.
///
/// Notably, all value types need to implement `Encode`, `Decode`, `MaxEncodedLen` and
/// `TypeInfo`, and possibly `Default`, if
/// [`ValueQuery`](frame_support::storage::types::ValueQuery) is used, explained in the
/// next section.
///
/// ### QueryKind
///
/// Every storage type mentioned above has a generic type called
/// [`QueryKind`](frame_support::storage::types::QueryKindTrait) that determines its
/// "query" type. This refers to the kind of value returned when querying the storage, for
/// instance, through a `::get()` method.
///
/// There are three types of queries:
///
/// 1. [`OptionQuery`](frame_support::storage::types::OptionQuery): The default query type.
/// It returns `Some(V)` if the value is present, or `None` if it isn't, where `V` is
/// the value type.
/// 2. [`ValueQuery`](frame_support::storage::types::ValueQuery): Returns the value itself
/// if present; otherwise, it returns `Default::default()`. This behavior can be
/// adjusted with the `OnEmpty` generic parameter, which defaults to `OnEmpty =
/// GetDefault`.
/// 3. [`ResultQuery`](frame_support::storage::types::ResultQuery): Returns `Result<V, E>`,
/// where `V` is the value type.
///
/// See [`QueryKind`](frame_support::storage::types::QueryKindTrait) for further examples.
///
/// ### Optimized Appending
///
/// All storage items — such as
/// [`StorageValue`](frame_support::storage::types::StorageValue),
/// [`StorageMap`](frame_support::storage::types::StorageMap), and their variants—offer an
/// `::append()` method optimized for collections. Using this method avoids the
/// inefficiency of decoding and re-encoding entire collections when adding items. For
/// instance, consider the storage declaration `type MyVal<T> = StorageValue<_, Vec<u8>,
/// ValueQuery>`. With `MyVal` storing a large list of bytes, `::append()` lets you
/// directly add bytes to the end in storage without processing the full list. Depending on
/// the storage type, additional key specifications may be needed.
///
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_append)]
/// Similarly, there also exists a `::try_append()` method, which can be used when handling
/// types where an append operation might fail, such as a
/// [`BoundedVec`](frame_support::BoundedVec).
///
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_try_append)]
/// ### Optimized Length Decoding
///
/// All storage items — such as
/// [`StorageValue`](frame_support::storage::types::StorageValue),
/// [`StorageMap`](frame_support::storage::types::StorageMap), and their counterparts —
/// incorporate the `::decode_len()` method. This method allows for efficient retrieval of
/// a collection's length without the necessity of decoding the entire dataset.
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_decode_len)]
/// ### Hashers
///
/// For all storage types, except
/// [`StorageValue`](frame_support::storage::types::StorageValue), a set of hashers needs
/// to be specified. The choice of hashers is crucial, especially in production chains. The
/// purpose of storage hashers in maps is to ensure the keys of a map are
/// uniformly distributed. An unbalanced map/trie can lead to inefficient performance.
///
/// In general, hashers are categorized as either cryptographically secure or not. The
/// former is slower than the latter. `Blake2` and `Twox` serve as examples of each,
/// respectively.
///
/// As a rule of thumb:
///
/// 1. If the map keys are not controlled by end users, or are cryptographically secure by
/// definition (e.g., `AccountId`), then the use of cryptographically secure hashers is NOT
/// required.
/// 2. If the map keys are controllable by the end users, cryptographically secure hashers
/// should be used.
///
/// For more information, look at the types that implement
/// [`frame_support::StorageHasher`](frame_support::StorageHasher).
///
/// Lastly, it's recommended for hashers with "concat" to have reversible hashes. Refer to
/// the implementors section of
/// [`hash::ReversibleStorageHasher`](frame_support::hash::ReversibleStorageHasher).
///
/// ### Prefixes
///
/// Internally, every storage type generates a "prefix". This prefix serves as the initial
/// segment of the key utilized to store values in the on-chain state (i.e., the final key
/// used in [`sp_io::storage`](sp_io::storage)). For all storage types, the following rule
/// applies:
///
/// > The storage prefix begins with `twox128(pallet_prefix) ++ twox128(STORAGE_PREFIX)`,
/// > where
/// > `pallet_prefix` is the name assigned to the pallet instance in
/// > [`frame_support::construct_runtime`](frame_support::construct_runtime), and
/// > `STORAGE_PREFIX` is the name of the `type` aliased to a particular storage type, such
/// > as
/// > `Foo` in `type Foo<T> = StorageValue<..>`.
///
/// For [`StorageValue`](frame_support::storage::types::StorageValue), no additional key is
/// required. For map types, the prefix is extended with one or more keys defined by the
/// map.
///
/// #### Example
#[doc = docify::embed!("src/lib.rs", example_storage_value_map_prefixes)]
/// ## Related Macros
///
/// The following attribute macros can be used in conjunction with the `#[storage]` macro:
///
/// * [`macro@getter`]: Creates a custom getter function.
/// * [`macro@storage_prefix`]: Overrides the default prefix of the storage item.
/// * [`macro@unbounded`]: Declares the storage item as unbounded.
/// * [`macro@disable_try_decode_storage`]: Declares that try-runtime checks should not
/// attempt to decode the storage item.
///
/// #### Example
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// /// A kitchen-sink StorageValue, with all possible additional attributes.
/// #[pallet::storage]
/// #[pallet::getter(fn foo)]
/// #[pallet::storage_prefix = "OtherFoo"]
/// #[pallet::unbounded]
/// #[pallet::disable_try_decode_storage]
/// pub type Foo<T> = StorageValue<_, u32, ValueQuery>;
/// }
/// ```
///
/// ## Note on deprecation of storage items
///
/// - Usage of `deprecated` attribute will propagate deprecation information to the pallet
/// metadata where the storage item was declared.
/// - For general usage examples of `deprecated` attribute please refer to <https://doc.rust-lang.org/nightly/reference/attributes/diagnostics.html#the-deprecated-attribute>
pub use frame_support_procedural::storage;
pub use frame_support_procedural::{
task_condition, task_index, task_list, task_weight, tasks_experimental,
};
/// Allows a pallet to declare a type as an origin.
///
/// If defined as such, this type will be amalgamated at the runtime level into
/// `RuntimeOrigin`, very similar to [`call`], [`error`] and [`event`]. See
/// [`composite_enum`] for similar cases.
///
/// Origin is a complex FRAME topics and is further explained in `polkadot_sdk_docs`.
///
/// ## Syntax Variants
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// /// On the spot declaration.
/// #[pallet::origin]
/// #[derive(PartialEq, Eq, Clone, RuntimeDebug, Encode, Decode, TypeInfo, MaxEncodedLen)]
/// pub enum Origin {
/// Foo,
/// Bar,
/// }
/// }
/// ```
///
/// Or, more commonly used:
///
/// ```
/// #[frame_support::pallet]
/// mod pallet {
/// # use frame_support::pallet_prelude::*;
/// # #[pallet::config]
/// # pub trait Config: frame_system::Config {}
/// # #[pallet::pallet]
/// # pub struct Pallet<T>(_);
/// #[derive(PartialEq, Eq, Clone, RuntimeDebug, Encode, Decode, TypeInfo, MaxEncodedLen)]
/// pub enum RawOrigin {
/// Foo,
/// Bar,
/// }
///
/// #[pallet::origin]
/// pub type Origin = RawOrigin;
/// }
/// ```
///
/// ## Warning
///
/// Modifying any pallet's origin type will cause the runtime level origin type to also
/// change in encoding. If stored anywhere on-chain, this will require a data migration.
///
/// Read more about origins at the [Origin Reference
/// Docs](../../polkadot_sdk_docs/reference_docs/frame_origin/index.html).
pub use frame_support_procedural::origin;
}
#[deprecated(note = "Will be removed after July 2023; Use `sp_runtime::traits` directly instead.")]
pub mod error {
#[doc(hidden)]
pub use sp_runtime::traits::{BadOrigin, LookupError};
}
#[doc(inline)]
pub use frame_support_procedural::register_default_impl;
// Generate a macro that will enable/disable code based on `std` feature being active.
sp_core::generate_feature_enabled_macro!(std_enabled, feature = "std", $);
// Generate a macro that will enable/disable code based on `try-runtime` feature being active.
sp_core::generate_feature_enabled_macro!(try_runtime_enabled, feature = "try-runtime", $);
sp_core::generate_feature_enabled_macro!(try_runtime_or_std_enabled, any(feature = "try-runtime", feature = "std"), $);
sp_core::generate_feature_enabled_macro!(try_runtime_and_std_not_enabled, all(not(feature = "try-runtime"), not(feature = "std")), $);
/// Helper for implementing GenesisBuilder runtime API
pub mod genesis_builder_helper;
/// Helper for generating the `RuntimeGenesisConfig` instance for presets.
pub mod generate_genesis_config;
#[cfg(test)]
mod test {
// use super::*;
use crate::{
hash::*,
storage::types::{StorageMap, StorageValue, ValueQuery},
traits::{ConstU32, StorageInstance},
BoundedVec,
};
use sp_io::{hashing::twox_128, TestExternalities};
struct Prefix;
impl StorageInstance for Prefix {
fn pallet_prefix() -> &'static str {
"test"
}
const STORAGE_PREFIX: &'static str = "foo";
}
struct Prefix1;
impl StorageInstance for Prefix1 {
fn pallet_prefix() -> &'static str {
"test"
}
const STORAGE_PREFIX: &'static str = "MyVal";
}
struct Prefix2;
impl StorageInstance for Prefix2 {
fn pallet_prefix() -> &'static str {
"test"
}
const STORAGE_PREFIX: &'static str = "MyMap";
}
#[docify::export]
#[test]
pub fn example_storage_value_try_append() {
type MyVal = StorageValue<Prefix, BoundedVec<u8, ConstU32<10>>, ValueQuery>;
TestExternalities::default().execute_with(|| {
MyVal::set(BoundedVec::try_from(vec![42, 43]).unwrap());
assert_eq!(MyVal::get(), vec![42, 43]);
// Try to append a single u32 to BoundedVec stored in `MyVal`
assert_ok!(MyVal::try_append(40));
assert_eq!(MyVal::get(), vec![42, 43, 40]);
});
}
#[docify::export]
#[test]
pub fn example_storage_value_append() {
type MyVal = StorageValue<Prefix, Vec<u8>, ValueQuery>;
TestExternalities::default().execute_with(|| {
MyVal::set(vec![42, 43]);
assert_eq!(MyVal::get(), vec![42, 43]);
// Append a single u32 to Vec stored in `MyVal`
MyVal::append(40);
assert_eq!(MyVal::get(), vec![42, 43, 40]);
});
}
#[docify::export]
#[test]
pub fn example_storage_value_decode_len() {
type MyVal = StorageValue<Prefix, BoundedVec<u8, ConstU32<10>>, ValueQuery>;
TestExternalities::default().execute_with(|| {
MyVal::set(BoundedVec::try_from(vec![42, 43]).unwrap());
assert_eq!(MyVal::decode_len().unwrap(), 2);
});
}
#[docify::export]
#[test]
pub fn example_storage_value_map_prefixes() {
type MyVal = StorageValue<Prefix1, u32, ValueQuery>;
type MyMap = StorageMap<Prefix2, Blake2_128Concat, u16, u32, ValueQuery>;
TestExternalities::default().execute_with(|| {
// This example assumes `pallet_prefix` to be "test"
// Get storage key for `MyVal` StorageValue
assert_eq!(
MyVal::hashed_key().to_vec(),
[twox_128(b"test"), twox_128(b"MyVal")].concat()
);
// Get storage key for `MyMap` StorageMap and `key` = 1
let mut k: Vec<u8> = vec![];
k.extend(&twox_128(b"test"));
k.extend(&twox_128(b"MyMap"));
k.extend(&1u16.blake2_128_concat());
assert_eq!(MyMap::hashed_key_for(1).to_vec(), k);
});
}
}