25 lines
470 B
Plaintext
25 lines
470 B
Plaintext
// Could possibly be forbidden by the parser instead if we have no intent to support that.
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pub fn choice(self: List<Option<a>>) -> Option<a> {
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when self is {
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[] -> None
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[Some(_) as result, ..] -> result
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[None, ..others] -> choice(others)
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}
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}
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test choice_1() {
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choice([Some(14), Some(42)]) == Some(14)
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}
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test choice_2() {
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choice([]) == None
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}
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test choice_3() {
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choice([None]) == None
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}
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test choice_4() {
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choice([None, Some(42)]) == Some(42)
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}
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