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- Closes eHealthExperts#39 - Closes eHealthExperts#38 - Closes eHealthExperts#34
When writing a `macro_rules! macro, any variables declared within the
right-hand side of a macro will inacessible to code expanded from a
metavariable. For example, the following code produces an error:
```rust
macro_rules! use_it {
($code:block) => {
let a = "25";
$code
}
}
fn main() {
use_it!({
let b = a;
});
}
```
Since 'let b = a' cannot access the 'a' variable defined within 'use_it'.
Due to a bug in the Rust compiler, this type of code was sometimes
when a proc-macro expansion occured near a `macro_rules!` expansion.
In this crate, the `test!` macro defines a local variable `it`, which is
then accessed from the `$steps:block` metavaraible.
This code will stop compiling in a future version of Rust (specifically,
once PR rust-lang/rust#77153 is merged).
I've adjusted the `test!` macro to take in a `$it:ident` metavariable,
which is used as the name of the local variable. To reduce churn, I've
made this optional - only one use of the `test!` macro needed to be
updated.
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When writing a `macro_rules! macro, any variables declared within the
right-hand side of a macro will inacessible to code expanded from a
metavariable. For example, the following code produces an error:
Since 'let b = a' cannot access the 'a' variable defined within 'use_it'.
Due to a bug in the Rust compiler, this type of code was sometimes
when a proc-macro expansion occured near a
macro_rules!expansion.In this crate, the
test!macro defines a local variableit, which isthen accessed from the
$steps:blockmetavaraible.This code will stop compiling in a future version of Rust (specifically,
once PR rust-lang/rust#77153 is merged).
I've adjusted the
test!macro to take in a$it:identmetavariable,which is used as the name of the local variable. To reduce churn, I've
made this optional - only one use of the
test!macro needed to beupdated.