48 lines
1.2 KiB
TypeScript
48 lines
1.2 KiB
TypeScript
//// [typeGuardsInExternalModule.ts]
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// Note that type guards affect types of variables and parameters only and
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// have no effect on members of objects such as properties.
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// local variable in external module
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var num: number;
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var var1: string | number;
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if (typeof var1 === "string") {
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num = var1.length; // string
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}
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else {
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num = var1; // number
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}
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// exported variable in external module
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var strOrNum: string | number;
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export var var2: string | number;
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if (typeof var2 === "string") {
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// export makes the var property and not variable
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strOrNum = var2; // string | number
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}
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else {
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strOrNum = var2; // number | string
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}
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//// [typeGuardsInExternalModule.js]
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// Note that type guards affect types of variables and parameters only and
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// have no effect on members of objects such as properties.
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"use strict";
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// local variable in external module
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var num;
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var var1;
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if (typeof var1 === "string") {
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num = var1.length; // string
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}
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else {
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num = var1; // number
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}
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// exported variable in external module
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var strOrNum;
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if (typeof exports.var2 === "string") {
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// export makes the var property and not variable
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strOrNum = exports.var2; // string | number
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}
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else {
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strOrNum = exports.var2; // number | string
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}
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