55 lines
869 B
TypeScript
55 lines
869 B
TypeScript
// @allowUnreachableCode: true
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let x: string | number | boolean | RegExp;
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let cond: boolean;
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x = /a/;
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if (x /* RegExp */, (x = true)) {
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x; // boolean
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x = "";
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}
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else {
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x; // boolean
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x = 42;
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}
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x; // string | number
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function a() {
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let x: string | number;
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if (cond) {
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x = 42;
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}
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else {
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x = "";
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return;
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}
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x; // number
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}
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function b() {
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let x: string | number;
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if (cond) {
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x = 42;
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throw "";
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}
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else {
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x = "";
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}
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x; // string
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}
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function c<T>(data: string | T): T {
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if (typeof data === 'string') {
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return JSON.parse(data);
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}
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else {
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return data;
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}
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}
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function d<T extends string>(data: string | T): never {
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if (typeof data === 'string') {
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throw new Error('will always happen');
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}
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else {
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return data;
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}
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}
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