16 lines
No EOL
234 B
TypeScript
16 lines
No EOL
234 B
TypeScript
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type S = "a" | "b";
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type T = S[] | S;
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function isS(t: T): t is S {
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return t === "a" || t === "b";
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}
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function f(foo: T) {
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if (isS(foo)) {
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return foo;
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}
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else {
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return foo[0];
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}
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} |