48 lines
1 KiB
Plaintext
48 lines
1 KiB
Plaintext
=== tests/cases/conformance/types/stringLiteral/stringLiteralCheckedInIf02.ts ===
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type S = "a" | "b";
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>S : "a" | "b"
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type T = S[] | S;
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>T : ("a" | "b")[] | "a" | "b"
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>S : "a" | "b"
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>S : "a" | "b"
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function isS(t: T): t is S {
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>isS : (t: ("a" | "b")[] | "a" | "b") => t is "a" | "b"
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>t : ("a" | "b")[] | "a" | "b"
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>T : ("a" | "b")[] | "a" | "b"
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>t : any
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>S : "a" | "b"
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return t === "a" || t === "b";
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>t === "a" || t === "b" : boolean
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>t === "a" : boolean
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>t : ("a" | "b")[] | "a" | "b"
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>"a" : string
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>t === "b" : boolean
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>t : ("a" | "b")[] | "a" | "b"
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>"b" : string
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}
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function f(foo: T) {
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>f : (foo: ("a" | "b")[] | "a" | "b") => "a" | "b"
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>foo : ("a" | "b")[] | "a" | "b"
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>T : ("a" | "b")[] | "a" | "b"
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if (isS(foo)) {
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>isS(foo) : boolean
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>isS : (t: ("a" | "b")[] | "a" | "b") => t is "a" | "b"
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>foo : ("a" | "b")[] | "a" | "b"
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return foo;
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>foo : "a" | "b"
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}
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else {
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return foo[0];
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>foo[0] : "a" | "b"
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>foo : ("a" | "b")[]
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>0 : number
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}
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}
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