54 lines
1.6 KiB
TypeScript
54 lines
1.6 KiB
TypeScript
//// [typeGuardsOnClassProperty.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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// Note that the class's property must be copied to a local variable for
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// the type guard to have an effect
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class D {
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data: string | string[];
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getData() {
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var data = this.data;
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return typeof data === "string" ? data : data.join(" ");
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}
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getData1() {
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return typeof this.data === "string" ? this.data : this.data.join(" ");
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}
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}
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var o: {
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prop1: number|string;
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prop2: boolean|string;
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} = {
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prop1: "string" ,
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prop2: true
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}
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if (typeof o.prop1 === "string" && o.prop1.toLowerCase()) {}
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var prop1 = o.prop1;
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if (typeof prop1 === "string" && prop1.toLocaleLowerCase()) { }
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//// [typeGuardsOnClassProperty.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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// Note that the class's property must be copied to a local variable for
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// the type guard to have an effect
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var D = (function () {
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function D() {
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}
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D.prototype.getData = function () {
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var data = this.data;
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return typeof data === "string" ? data : data.join(" ");
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};
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D.prototype.getData1 = function () {
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return typeof this.data === "string" ? this.data : this.data.join(" ");
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};
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return D;
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})();
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var o = {
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prop1: "string",
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prop2: true
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};
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if (typeof o.prop1 === "string" && o.prop1.toLowerCase()) { }
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var prop1 = o.prop1;
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if (typeof prop1 === "string" && prop1.toLocaleLowerCase()) { }
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