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// Test that we infer the expected type of a pattern to an array of the given length.
#![allow(unused_variables)]
use std::array::TryFromSliceError;
use std::convert::TryInto;
struct Zeroes;
impl Into<[usize; 2]> for Zeroes {
fn into(self) -> [usize; 2] {
[0; 2]
}
}
impl Into<[usize; 3]> for Zeroes {
fn into(self) -> [usize; 3] {
[0; 3]
}
}
impl Into<[usize; 4]> for Zeroes {
fn into(self) -> [usize; 4] {
[0; 4]
}
}
fn zeroes_into() {
let [a, b, c] = Zeroes.into();
let [d, e, f]: [_; 3] = Zeroes.into();
}
fn array_try_from(x: &[usize]) -> Result<usize, TryFromSliceError> {
let [a, b] = x.try_into()?;
Ok(a + b)
}
fn destructuring_assignment() {
let a: i32;
let b;
[a, b] = Default::default();
}
fn test_nested_array() {
let a: [_; 3];
let b;
//~^ ERROR type annotations needed
[a, b] = Default::default();
}
fn test_nested_array_type_hint() {
let a: [_; 3];
let b;
[a, b] = Default::default();
let _: i32 = b[1];
}
fn test_working_nested_array() {
let a: i32;
[[a, _, _], _, _] = Default::default();
}
struct Foo<T>([T; 2]);
impl<T: Default + Copy> Default for Foo<T> {
fn default() -> Self {
Foo([Default::default(); 2])
}
}
fn field_array() {
let a: i32;
let b;
Foo([a, b]) = Default::default();
}
fn main() {}
|
