34 lines
710 B
Rust
34 lines
710 B
Rust
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fn foldl<T, U: Copy>(
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values: &[T],
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initial: U,
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function: &fn(partial: U, element: &T) -> U
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) -> U {
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match values {
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[head, ..tail] =>
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foldl(tail, function(initial, &head), function),
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_ => copy initial
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}
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}
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fn main() {
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let x = [1, 2, 3, 4, 5];
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match x {
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[a, b, c, d, e, f] => {
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core::util::unreachable();
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}
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[a, b, c, d, e] => {
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assert a == 1;
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assert b == 2;
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assert c == 3;
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assert d == 4;
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assert e == 5;
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}
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_ => {
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core::util::unreachable();
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}
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}
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let product = foldl(x, 1, |a, b| a * *b);
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assert product == 120;
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}
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