rust/tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs
Matthew Jasper 333388fd3c Move let expression checking to parsing
There was an incomplete version of the check in parsing and a second
version in AST validation. This meant that some, but not all, invalid
uses were allowed inside macros/disabled cfgs. It also means that later
passes have a hard time knowing when the let expression is in a valid
location, sometimes causing ICEs.

- Add a field to ExprKind::Let in AST/HIR to mark whether it's in a
  valid location.
- Suppress later errors and MIR construction for invalid let
  expressions.
2023-09-11 15:51:18 +00:00

26 lines
646 B
Rust

// Parenthesised let "expressions" are not allowed in guards
#![feature(if_let_guard)]
#![feature(let_chains)]
#[cfg(FALSE)]
fn un_cfged() {
match () {
() if let 0 = 1 => {}
() if (let 0 = 1) => {}
//~^ ERROR expected expression, found `let` statement
() if (((let 0 = 1))) => {}
//~^ ERROR expected expression, found `let` statement
}
}
fn main() {
match () {
() if let 0 = 1 => {}
() if (let 0 = 1) => {}
//~^ ERROR expected expression, found `let` statement
() if (((let 0 = 1))) => {}
//~^ ERROR expected expression, found `let` statement
}
}