21 lines
429 B
Rust
21 lines
429 B
Rust
// xfail-stage0
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fn fix_help[A,B](@fn (@fn (&A) -> B, &A) -> B f, &A x) -> B {
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ret f(@bind fix_help(f, _), x);
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}
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fn fix[A,B](@fn (@fn (&A) -> B, &A) -> B f) -> (@fn(&A) -> B) {
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ret @bind fix_help(f, _);
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}
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fn fact_(@fn (&int) -> int f, &int n) -> int {
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// fun fact 0 = 1
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ret if (n == 0) { 1 } else { n*f(n-1) };
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}
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fn main() {
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auto fact = fix(@fact_);
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assert(fact(5) == 120);
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assert(fact(2) == 2);
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}
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