rust/tests/ui/hygiene/hygienic-label-2.rs

macro_rules! foo {
    ($e: expr) => { 'x: loop { $e } }
}

pub fn main() {
    foo!(break 'x); //~ ERROR use of undeclared label `'x`
}
Make break and continue hygienic Makes labelled loops hygiene by performing renaming of the labels defined in e.g. `'x: loop { ... }` and then used in break and continue statements within loop body so that they act hygienically when used with macros. Closes #12262. 2014-02-15 16:54:32 +08:00			`macro_rules! foo {`
			`($e: expr) => { 'x: loop { $e } }`
			`}`

			`pub fn main() {`
librustc: Fix the issue with labels shadowing variable names by making the leading quote part of the identifier for the purposes of hygiene. This adopts @jbclements' solution to #14539. I'm not sure if this is a breaking change or not. Closes #12512. [breaking-change] 2014-06-11 04:54:13 +08:00			foo!(break 'x); //~ ERROR use of undeclared label `'x`
Make break and continue hygienic Makes labelled loops hygiene by performing renaming of the labels defined in e.g. `'x: loop { ... }` and then used in break and continue statements within loop body so that they act hygienically when used with macros. Closes #12262. 2014-02-15 16:54:32 +08:00			`}`