rust/tests/ui/rfcs/rfc-2497-if-let-chains/ast-validate-guards.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

24 lines
496 B
Rust

#![feature(let_chains)]
fn let_or_guard(x: Result<Option<i32>, ()>) {
match x {
Ok(opt) if let Some(4) = opt || false => {}
//~^ ERROR expected expression, found `let` statement
_ => {}
}
}
fn hiding_unsafe_mod(x: Result<Option<i32>, ()>) {
match x {
Ok(opt)
if {
unsafe mod a {};
//~^ ERROR module cannot be declared unsafe
false
} => {}
_ => {}
}
}
fn main() {}