about summary refs log tree commit diff
path: root/compiler/rustc_error_codes/src/error_codes/E0466.md
blob: 28016eb395e970cc00fa2b30af4357a9cd8c8815 (plain)
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
#### Note: this error code is no longer emitted by the compiler.

Macro import declaration was malformed.

Erroneous code examples:

```compile_fail
#[macro_use(a_macro(another_macro))] // error: invalid import declaration
extern crate core as some_crate;

#[macro_use(i_want = "some_macros")] // error: invalid import declaration
extern crate core as another_crate;
```

This is a syntax error at the level of attribute declarations. The proper
syntax for macro imports is the following:

```ignore (cannot-doctest-multicrate-project)
// In some_crate:
#[macro_export]
macro_rules! get_tacos {
    ...
}

#[macro_export]
macro_rules! get_pimientos {
    ...
}

// In your crate:
#[macro_use(get_tacos, get_pimientos)] // It imports `get_tacos` and
extern crate some_crate;               // `get_pimientos` macros from some_crate
```

If you would like to import all exported macros, write `macro_use` with no
arguments.