Use local_inner_macros to resolve all local macros within $crate #288
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This fixes the following error when using Rust 2018 style macro imports.
use log::info;
fn main() {
info!("...");
}
error: cannot find macro `log!` in this scope
--> src/main.rs:4:5
|
4 | info!("...");
| ^^^^^^^^^^^^^
The `local_inner_macros` modifier resolves all macro invocations made
from within that macro as macros in the same crate. So if `info!`
expands to an invocation of `log!` then this would be resolved as
`$crate::log!` rather than requiring the caller to have `log` in scope.
The attribute is ignored by pre-2018 compilers so log 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
`$crate::` prefixes on invocations of local macros.
alexcrichton
approved these changes
Aug 17, 2018
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This fixes the following error when using Rust 2018 style macro imports.
The
local_inner_macrosmodifier resolves all macro invocations made from within that macro as macros in the same crate. So ifinfo!expands to an invocation oflog!then this would be resolved as$crate::log!rather than requiring the caller to havelogin scope.The attribute is ignored by pre-2018 compilers so log 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 local macros.Fixes #54.