Module frame_support::pallet_prelude

Prelude to be used alongside pallet macro, for ease of use.

Re-exports

• pub use crate::dispatch::DispatchClass;
• pub use crate::dispatch::DispatchResult;
• pub use crate::dispatch::DispatchResultWithPostInfo;
• pub use crate::dispatch::Parameter;
• pub use crate::dispatch::Pays;
• pub use crate::inherent::ProvideInherent;
• pub use crate::storage;
• pub use crate::storage::types::OptionQuery;
• pub use crate::storage::types::ResultQuery;
• pub use crate::storage::types::ValueQuery;
• pub use frame_support::pallet_macros::*;

Macros

• ensure
  Evaluate $x:expr and if not true return Err($y:expr).

Structs

• Blake2_128
  Hash storage keys with blake2 128
• Blake2_128Concat
  Hash storage keys with concat(blake2_128(key), key)
• Blake2_256
  Hash storage keys with blake2 256
• BoundedVec
  A bounded vector.
• ConstU32
  Const getter for a basic type.
• CountedStorageMap
  A wrapper around a StorageMap and a StorageValue<Value=u32> to keep track of how many items are in a map, without needing to iterate all the values.
• GetDefault
  Implement Get by returning Default for any type that implements Default.
• Identity
  Store the key directly.
• InherentData
  Inherent data to include in a block.
• NMapKey
  A type used exclusively by storage maps as their key type.
• PhantomData
  Zero-sized type used to mark things that “act like” they own a T.
• StorageDoubleMap
  A type that allow to store values for (key1, key2) couple. Similar to StorageMap but allow to iterate and remove value associated to first key.
• StorageMap
  A type that allow to store value for given key. Allowing to insert/remove/iterate on values.
• StorageNMap
  A type that allow to store values for an arbitrary number of keys in the form of (Key<Hasher1, key1>, Key<Hasher2, key2>, ..., Key<HasherN, keyN>).
• StorageValue
  A type that allow to store a value.
• StorageVersion
  The storage version of a pallet.
• Twox64Concat
  Hash storage keys with concat(twox64(key), key)
• Twox128
  Hash storage keys with twox 128
• Twox256
  Hash storage keys with twox 256
• ValidTransaction
  Information concerning a valid transaction.
• Weight

Enums

• DispatchError
  Reason why a dispatch call failed.
• InvalidTransaction
  An invalid transaction validity.
• TransactionSource
  The source of the transaction.
• TransactionValidityError
  Errors that can occur while checking the validity of a transaction.
• UnknownTransaction
  An unknown transaction validity.

Constants

• MAX_MODULE_ERROR_ENCODED_SIZE
  The number of bytes of the module-specific error field defined in ModuleError. In FRAME, this is the maximum encoded size of a pallet error type.

Traits

• Decode
  Trait that allows zero-copy read of value-references from slices in LE format.
• Encode
  Trait that allows zero-copy write of value-references to slices in LE format.
• EnsureOrigin
  Some sort of check on the origin is performed by this object.
• GenesisBuild
  A trait to define the build function of a genesis config, T and I are placeholder for pallet trait and pallet instance.
• Get
  A trait for querying a single value from a type.
• GetStorageVersion
  Provides information about the storage version of a pallet.
• Hooks
  The pallet hooks trait. Implementing this lets you express some logic to execute.
• IsType
  Trait to be used when types are exactly same.
• MaxEncodedLen
  Items implementing MaxEncodedLen have a statically known maximum encoded size.
• MaybeSerializeDeserialize
  A type that implements Serialize, DeserializeOwned and Debug when in std environment or serde feature is activated.
• Member
  A type that can be used in runtime structures.
• PalletInfoAccess
  Provides information about the pallet itself and its setup in the runtime.
• StorageInfoTrait
  A trait to give information about storage.
• TypeInfo
  Implementors return their meta type information.
• TypedGet
  A trait for querying a single value from a type defined in the trait.
• ValidateUnsigned
  Provide validation for unsigned extrinsics.

Type Definitions

• InherentIdentifier
  An identifier for an inherent.
• TransactionLongevity
  Minimum number of blocks a transaction will remain valid for. TransactionLongevity::max_value() means “forever”.
• TransactionPriority
  Priority for a transaction. Additive. Higher is better.
• TransactionTag
  Tag for a transaction. No two transactions with the same tag should be placed on-chain.
• TransactionValidity
  Information on a transaction’s validity and, if valid, on how it relates to other transactions.

Attribute Macros

• register_default_impl
  Attach this attribute to an impl statement that you want to use with #[derive_impl(..)].

Derive Macros

• CloneNoBound
  Derive Clone but do not bound any generic. Docs are at frame_support::CloneNoBound.
• DebugNoBound
  Derive Debug but do not bound any generics. Docs are at frame_support::DebugNoBound.
• Decode
  Derive parity_scale_codec::Decode and for struct and enum.
• Encode
  Derive parity_scale_codec::Encode and parity_scale_codec::EncodeLike for struct and enum.
• EqNoBound
  derive Eq but do no bound any generic. Docs are at frame_support::EqNoBound.
• MaxEncodedLen
  Derive parity_scale_codec::MaxEncodedLen for struct and enum.
• PartialEqNoBound
  Derive PartialEq but do not bound any generic. Docs are at frame_support::PartialEqNoBound.
• RuntimeDebug
• RuntimeDebugNoBound
  Derive [Debug], if std is enabled it uses frame_support::DebugNoBound, if std is not enabled it just returns "<wasm:stripped>". This behaviour is useful to prevent bloating the runtime WASM blob from unneeded code.
• TypeInfo