40 lines
879 B
Rust
40 lines
879 B
Rust
static FOO: fn() = || assert_ne!(42, 43);
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static BAR: fn(i32, i32) = |a, b| assert_ne!(a, b);
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// use to first make the closure FnOnce() before making it fn()
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fn force_once0<R, F: FnOnce() -> R>(f: F) -> F {
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f
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}
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fn force_once1<T, R, F: FnOnce(T) -> R>(f: F) -> F {
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f
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}
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fn force_mut0<R, F: FnMut() -> R>(f: F) -> F {
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f
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}
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fn force_mut1<T, R, F: FnMut(T) -> R>(f: F) -> F {
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f
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}
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fn main() {
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FOO();
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BAR(44, 45);
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let bar: unsafe fn(i32, i32) = BAR;
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unsafe { bar(46, 47) };
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let boo: &dyn Fn(i32, i32) = &BAR;
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boo(48, 49);
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let f: fn() = || {};
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f();
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let f = force_once0(|| {}) as fn();
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f();
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let f = force_mut0(|| {}) as fn();
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f();
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let g: fn(i32) = |i| assert_eq!(i, 2);
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g(2);
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let g = force_once1(|i| assert_eq!(i, 2)) as fn(i32);
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g(2);
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let g = force_mut1(|i| assert_eq!(i, 2)) as fn(i32);
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g(2);
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}
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