Use local_inner_macros to resolve all helper macros within $crate #107
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This fixes the following error when using Rust 2018 style macro imports.
extern crate lazy_static;
use lazy_static::lazy_static;
error: cannot find macro `__lazy_static_internal!` in this scope
--> src/main.rs:8:1
|
8 | / lazy_static! {
9 | | static ref M: HashMap<String, String> = HashMap::new();
10 | | }
| |_^
|
The `local_inner_macros` modifier resolves all macro invocations made
from within that macro as helpers in the same crate. So if
`lazy_static!` expands to an invocation of `__lazy_static_internal!`
then this would be resolved as `$crate::__lazy_static_internal!` rather
than requiring the caller to have `__lazy_static_internal` in scope.
The attribute is ignored by pre-2018 compilers so lazy_static will
continue to work as normal with #[macro_use].
In the future when dropping compatibility with pre-2018 compilers we can
remove the `local_inner_macros` modifier and use our own explicit
`$crate::` prefixes on invocations of helper macros.
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This fixes the following error when using Rust 2018 style macro imports.
The
local_inner_macrosmodifier resolves all macro invocations made from within that macro as helpers in the same crate. So iflazy_static!expands to an invocation of__lazy_static_internal!then this would be resolved as$crate::__lazy_static_internal!rather than requiring the caller to have__lazy_static_internalin scope.The attribute is ignored by pre-2018 compilers so lazy_static will continue to work as normal with
#[macro_use].In the future when dropping compatibility with pre-2018 compilers we can remove the
local_inner_macrosmodifier and use our own explicit$crate::prefixes on invocations of helper macros.