35 lines
731 B
Rust
35 lines
731 B
Rust
#![feature(box_syntax)]
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fn make_box() -> Box<(i16, i16)> {
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Box::new((1, 2))
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}
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fn make_box_syntax() -> Box<(i16, i16)> {
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box (1, 2)
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}
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fn allocate_reallocate() {
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let mut s = String::new();
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// 6 byte heap alloc (__rust_allocate)
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s.push_str("foobar");
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assert_eq!(s.len(), 6);
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assert_eq!(s.capacity(), 6);
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// heap size doubled to 12 (__rust_reallocate)
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s.push_str("baz");
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assert_eq!(s.len(), 9);
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assert_eq!(s.capacity(), 12);
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// heap size reduced to 9 (__rust_reallocate)
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s.shrink_to_fit();
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assert_eq!(s.len(), 9);
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assert_eq!(s.capacity(), 9);
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}
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fn main() {
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assert_eq!(*make_box(), (1, 2));
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assert_eq!(*make_box_syntax(), (1, 2));
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allocate_reallocate();
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}
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