AD
Size: a a a
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AD
w
w
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AD
キ
w
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const foo: [string] = ['test']; // ok
const bar: [string] = ['foo', 'bar']; // error
const baz: string[] = ['foo', 'bar']; // okDC

キ
<T extends boolean>(asNumber: T = false): T extends true ? number : stringキ
キ
T extends true | falseDC
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