23 lines
387 B
Plaintext
23 lines
387 B
Plaintext
enum Option { Some(i64), None }
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fn main() -> i64 {
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let s = Option::Some(42);
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let n = Option::None;
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// if let: 匹配 Some
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if let Option::Some = s {
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print_i64(100);
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} else {
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print_i64(0);
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}
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// if let: 匹配 None（走 else）
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if let Option::Some = n {
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print_i64(999);
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} else {
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print_i64(200);
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}
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return 0;
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}
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