tt_call/
unexpected.rs

1/// Fail due to an unexpected input token.
2///
3/// The compiler's error will indicate the source of the unexpected token to the
4/// user.
5///
6/// ```compile_fail
7/// use tt_call::error_unexpected;
8///
9/// fn main() {
10///     error_unexpected! { true }
11/// }
12/// ```
13///
14/// ```text
15/// error: no rules expected the token `true`
16///  --> src/unexpected.rs:5:25
17///   |
18/// 5 |     error_unexpected! { true }
19///   |                         ^^^^
20/// ```
21#[macro_export]
22macro_rules! error_unexpected {
23    ($($tokens:tt)+) => {
24        $crate::private_unexpected! {
25            $($tokens)*
26        }
27    };
28}
29
30#[doc(hidden)]
31#[macro_export]
32macro_rules! private_unexpected {
33    () => {};
34}
35
36/// Fail due to an unexpected end of input.
37///
38/// The resulting compiler error is typically not good. Always prefer to use
39/// `error_unexpected!` or `error_unexpected_last!` if there are tokens on which
40/// an error could reasonably be triggered.
41///
42/// ```compile_fail
43/// use tt_call::error_eof;
44///
45/// fn main() {
46///     error_eof!{}
47/// }
48/// ```
49///
50/// ```text
51/// error: unexpected end of macro invocation
52///  --> src/unexpected.rs:5:5
53///   |
54/// 5 |     error_eof!{}
55///   |     ^^^^^^^^^^^^
56/// ```
57#[macro_export]
58macro_rules! error_eof {
59    () => {
60        $crate::private_eof! {}
61    };
62}
63
64#[doc(hidden)]
65#[macro_export]
66macro_rules! private_eof {
67    ($never:tt) => {};
68}
69
70/// Fail due to an unexpected input token, faulting the last token.
71///
72/// The compiler's error will indicate the source of the unexpected token to the
73/// user.
74///
75/// ```compile_fail
76/// use tt_call::error_unexpected_last;
77///
78/// fn main() {
79///     error_unexpected_last! { aaa bbb ccc }
80/// }
81/// ```
82///
83/// ```text
84/// error: no rules expected the token `true`
85///  --> src/unexpected.rs:5:38
86///   |
87/// 5 |     error_unexpected_last! { aaa bbb ccc }
88///   |                                      ^^^
89/// ```
90#[macro_export]
91macro_rules! error_unexpected_last {
92    ($($tokens:tt)+) => {
93        $crate::private_unexpected_last! {
94            $($tokens)*
95        }
96    };
97}
98
99#[doc(hidden)]
100#[macro_export]
101macro_rules! private_unexpected_last {
102    ($last:tt) => {
103        $crate::error_unexpected! {
104            $last
105        }
106    };
107
108    ($skip:tt $($rest:tt)*) => {
109        $crate::private_unexpected_last! {
110            $($rest)*
111        }
112    };
113}
114
115#[doc(hidden)]
116#[macro_export]
117macro_rules! private_unexpected_close_empty_square_brackets {
118    ([_]) => {};
119}
120
121#[doc(hidden)]
122#[macro_export]
123macro_rules! private_unexpected_close_square_bracket_after_ty_semicolon {
124    ([$ty:ty; _]) => {};
125}
tt_call/unexpected.rs

tt_call/
unexpected.rs
