166 lines
5.8 KiB
TypeScript
166 lines
5.8 KiB
TypeScript
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//// [typeGuardsInFunction.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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// variables in global
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var num: number;
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var var1: string | number;
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// Inside function declaration
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function f(param: string | number) {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables in function declaration
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var var2: string | number;
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num = typeof var2 === "string" && var2.length; // string
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// parameters in function declaration
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num = typeof param === "string" && param.length; // string
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}
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// local function declaration
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function f1(param: string | number) {
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var var2: string | number;
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function f2(param1: string | number) {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables from outer function declaration
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num = typeof var2 === "string" && var2.length; // string
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// parameters in outer declaration
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num = typeof param === "string" && param.length; // string
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// local
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var var3: string | number;
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num = typeof var3 === "string" && var3.length; // string
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num = typeof param1 === "string" && param1.length; // string
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}
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}
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// Function expression
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function f2(param: string | number) {
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// variables in function declaration
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var var2: string | number;
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// variables in function expressions
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var r = function (param1: string | number) {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables from outer function declaration
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num = typeof var2 === "string" && var2.length; // string
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// parameters in outer declaration
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num = typeof param === "string" && param.length; // string
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// local
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var var3: string | number;
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num = typeof var3 === "string" && var3.length; // string
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num = typeof param1 === "string" && param1.length; // string
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} (param);
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}
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// Arrow expression
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function f3(param: string | number) {
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// variables in function declaration
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var var2: string | number;
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// variables in function expressions
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var r = ((param1: string | number) => {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables from outer function declaration
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num = typeof var2 === "string" && var2.length; // string
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// parameters in outer declaration
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num = typeof param === "string" && param.length; // string
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// local
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var var3: string | number;
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num = typeof var3 === "string" && var3.length; // string
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num = typeof param1 === "string" && param1.length; // string
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})(param);
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}
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// Return type of function
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// Inside function declaration
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var strOrNum: string | number;
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function f4() {
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var var2: string | number = strOrNum;
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return var2;
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}
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strOrNum = typeof f4() === "string" && f4(); // string | number
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//// [typeGuardsInFunction.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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// variables in global
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var num;
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var var1;
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// Inside function declaration
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function f(param) {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables in function declaration
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var var2;
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num = typeof var2 === "string" && var2.length; // string
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// parameters in function declaration
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num = typeof param === "string" && param.length; // string
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}
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// local function declaration
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function f1(param) {
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var var2;
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function f2(param1) {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables from outer function declaration
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num = typeof var2 === "string" && var2.length; // string
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// parameters in outer declaration
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num = typeof param === "string" && param.length; // string
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// local
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var var3;
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num = typeof var3 === "string" && var3.length; // string
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num = typeof param1 === "string" && param1.length; // string
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}
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}
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// Function expression
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function f2(param) {
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// variables in function declaration
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var var2;
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// variables in function expressions
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var r = function (param1) {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables from outer function declaration
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num = typeof var2 === "string" && var2.length; // string
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// parameters in outer declaration
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num = typeof param === "string" && param.length; // string
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// local
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var var3;
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num = typeof var3 === "string" && var3.length; // string
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num = typeof param1 === "string" && param1.length; // string
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}(param);
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}
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// Arrow expression
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function f3(param) {
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// variables in function declaration
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var var2;
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// variables in function expressions
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var r = (function (param1) {
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// global vars in function declaration
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num = typeof var1 === "string" && var1.length; // string
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// variables from outer function declaration
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num = typeof var2 === "string" && var2.length; // string
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// parameters in outer declaration
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num = typeof param === "string" && param.length; // string
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// local
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var var3;
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num = typeof var3 === "string" && var3.length; // string
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num = typeof param1 === "string" && param1.length; // string
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})(param);
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}
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// Return type of function
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// Inside function declaration
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var strOrNum;
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function f4() {
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var var2 = strOrNum;
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return var2;
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}
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strOrNum = typeof f4() === "string" && f4(); // string | number
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