mirror of https://github.com/rust-lang/rust
40 lines
948 B
Rust
40 lines
948 B
Rust
//@ run-pass
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#![allow(dead_code)]
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#![allow(unused_variables)]
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// Type ascription doesn't lead to unsoundness
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#![feature(type_ascription)]
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use std::mem;
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const C1: u8 = type_ascribe!(10, u8);
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const C2: [u8; type_ascribe!(1, usize)] = [1];
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struct S {
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a: u8
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}
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fn main() {
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assert_eq!(type_ascribe!(C1.into(), i32), 10);
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assert_eq!(C2[0], 1);
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let s = S { a: type_ascribe!(10, u8) };
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let arr = &[1u8, 2, 3];
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let mut v = type_ascribe!(arr.iter().cloned().collect(), Vec<_>);
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v.push(4);
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assert_eq!(v, [1, 2, 3, 4]);
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let a = type_ascribe!(1, u8);
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let b = type_ascribe!(a.into(), u16);
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assert_eq!(v[type_ascribe!(a.into(), usize)], 2);
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assert_eq!(mem::size_of_val(&a), 1);
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assert_eq!(mem::size_of_val(&b), 2);
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assert_eq!(b, type_ascribe!(1, u16));
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let mut v = Vec::new();
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type_ascribe!(v, Vec<u8>) = vec![1, 2, 3]; // Place expression type ascription
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assert_eq!(v, [1u8, 2, 3]);
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}
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