11 lines
195 B
Plaintext
11 lines
195 B
Plaintext
pub fn map(opt: Option<a>, f: fn(a) -> result) -> Option<result> {
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when opt is {
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None -> None
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Some(a) -> Some(f(a))
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}
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}
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test map_2() {
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map(Some(14), fn(n) { n + 1 }) == Some(15)
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}
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