mirror of
https://github.com/rust-lang/rust.git
synced 2025-10-02 18:27:37 +00:00
24 lines
564 B
Rust
24 lines
564 B
Rust
//! Tests that mutation of captured immutable variables in closures are not permitted.
|
|
|
|
#![feature(unboxed_closures, tuple_trait)]
|
|
|
|
use std::io::Read;
|
|
|
|
fn to_fn_once<A: std::marker::Tuple, F: FnOnce<A>>(f: F) -> F {
|
|
f
|
|
}
|
|
|
|
fn main() {
|
|
let x = 1;
|
|
to_fn_once(move || {
|
|
x = 2;
|
|
//~^ ERROR: cannot assign to `x`, as it is not declared as mutable
|
|
});
|
|
|
|
let s = std::io::stdin();
|
|
to_fn_once(move || {
|
|
s.read_to_end(&mut Vec::new());
|
|
//~^ ERROR: cannot borrow `s` as mutable, as it is not declared as mutable
|
|
});
|
|
}
|