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|
=== tests/cases/conformance/expressions/typeGuards/typeGuardsInFunction.ts ===
// Note that type guards affect types of variables and parameters only and
// have no effect on members of objects such as properties.
// variables in global
var num: number;
>num : number
var var1: string | number;
>var1 : string | number
// Inside function declaration
function f(param: string | number) {
>f : (param: string | number) => void
>param : string | number
// global vars in function declaration
num = typeof var1 === "string" && var1.length; // string
>num = typeof var1 === "string" && var1.length : number
>num : number
>typeof var1 === "string" && var1.length : number
>typeof var1 === "string" : boolean
>typeof var1 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var1 : string | number
>"string" : "string"
>var1.length : number
>var1 : string
>length : number
// variables in function declaration
var var2: string | number;
>var2 : string | number
num = typeof var2 === "string" && var2.length; // string
>num = typeof var2 === "string" && var2.length : number
>num : number
>typeof var2 === "string" && var2.length : number
>typeof var2 === "string" : boolean
>typeof var2 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var2 : string | number
>"string" : "string"
>var2.length : number
>var2 : string
>length : number
// parameters in function declaration
num = typeof param === "string" && param.length; // string
>num = typeof param === "string" && param.length : number
>num : number
>typeof param === "string" && param.length : number
>typeof param === "string" : boolean
>typeof param : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>param : string | number
>"string" : "string"
>param.length : number
>param : string
>length : number
}
// local function declaration
function f1(param: string | number) {
>f1 : (param: string | number) => void
>param : string | number
var var2: string | number;
>var2 : string | number
function f2(param1: string | number) {
>f2 : (param1: string | number) => void
>param1 : string | number
// global vars in function declaration
num = typeof var1 === "string" && var1.length; // string
>num = typeof var1 === "string" && var1.length : number
>num : number
>typeof var1 === "string" && var1.length : number
>typeof var1 === "string" : boolean
>typeof var1 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var1 : string | number
>"string" : "string"
>var1.length : number
>var1 : string
>length : number
// variables from outer function declaration
num = typeof var2 === "string" && var2.length; // string
>num = typeof var2 === "string" && var2.length : number
>num : number
>typeof var2 === "string" && var2.length : number
>typeof var2 === "string" : boolean
>typeof var2 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var2 : string | number
>"string" : "string"
>var2.length : number
>var2 : string
>length : number
// parameters in outer declaration
num = typeof param === "string" && param.length; // string
>num = typeof param === "string" && param.length : number
>num : number
>typeof param === "string" && param.length : number
>typeof param === "string" : boolean
>typeof param : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>param : string | number
>"string" : "string"
>param.length : number
>param : string
>length : number
// local
var var3: string | number;
>var3 : string | number
num = typeof var3 === "string" && var3.length; // string
>num = typeof var3 === "string" && var3.length : number
>num : number
>typeof var3 === "string" && var3.length : number
>typeof var3 === "string" : boolean
>typeof var3 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var3 : string | number
>"string" : "string"
>var3.length : number
>var3 : string
>length : number
num = typeof param1 === "string" && param1.length; // string
>num = typeof param1 === "string" && param1.length : number
>num : number
>typeof param1 === "string" && param1.length : number
>typeof param1 === "string" : boolean
>typeof param1 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>param1 : string | number
>"string" : "string"
>param1.length : number
>param1 : string
>length : number
}
}
// Function expression
function f2(param: string | number) {
>f2 : (param: string | number) => void
>param : string | number
// variables in function declaration
var var2: string | number;
>var2 : string | number
// variables in function expressions
var r = function (param1: string | number) {
>r : void
>function (param1: string | number) { // global vars in function declaration num = typeof var1 === "string" && var1.length; // string // variables from outer function declaration num = typeof var2 === "string" && var2.length; // string // parameters in outer declaration num = typeof param === "string" && param.length; // string // local var var3: string | number; num = typeof var3 === "string" && var3.length; // string num = typeof param1 === "string" && param1.length; // string } (param) : void
>function (param1: string | number) { // global vars in function declaration num = typeof var1 === "string" && var1.length; // string // variables from outer function declaration num = typeof var2 === "string" && var2.length; // string // parameters in outer declaration num = typeof param === "string" && param.length; // string // local var var3: string | number; num = typeof var3 === "string" && var3.length; // string num = typeof param1 === "string" && param1.length; // string } : (param1: string | number) => void
>param1 : string | number
// global vars in function declaration
num = typeof var1 === "string" && var1.length; // string
>num = typeof var1 === "string" && var1.length : number
>num : number
>typeof var1 === "string" && var1.length : number
>typeof var1 === "string" : boolean
>typeof var1 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var1 : string | number
>"string" : "string"
>var1.length : number
>var1 : string
>length : number
// variables from outer function declaration
num = typeof var2 === "string" && var2.length; // string
>num = typeof var2 === "string" && var2.length : number
>num : number
>typeof var2 === "string" && var2.length : number
>typeof var2 === "string" : boolean
>typeof var2 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var2 : string | number
>"string" : "string"
>var2.length : number
>var2 : string
>length : number
// parameters in outer declaration
num = typeof param === "string" && param.length; // string
>num = typeof param === "string" && param.length : number
>num : number
>typeof param === "string" && param.length : number
>typeof param === "string" : boolean
>typeof param : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>param : string | number
>"string" : "string"
>param.length : number
>param : string
>length : number
// local
var var3: string | number;
>var3 : string | number
num = typeof var3 === "string" && var3.length; // string
>num = typeof var3 === "string" && var3.length : number
>num : number
>typeof var3 === "string" && var3.length : number
>typeof var3 === "string" : boolean
>typeof var3 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var3 : string | number
>"string" : "string"
>var3.length : number
>var3 : string
>length : number
num = typeof param1 === "string" && param1.length; // string
>num = typeof param1 === "string" && param1.length : number
>num : number
>typeof param1 === "string" && param1.length : number
>typeof param1 === "string" : boolean
>typeof param1 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>param1 : string | number
>"string" : "string"
>param1.length : number
>param1 : string
>length : number
} (param);
>param : string | number
}
// Arrow expression
function f3(param: string | number) {
>f3 : (param: string | number) => void
>param : string | number
// variables in function declaration
var var2: string | number;
>var2 : string | number
// variables in function expressions
var r = ((param1: string | number) => {
>r : void
>((param1: string | number) => { // global vars in function declaration num = typeof var1 === "string" && var1.length; // string // variables from outer function declaration num = typeof var2 === "string" && var2.length; // string // parameters in outer declaration num = typeof param === "string" && param.length; // string // local var var3: string | number; num = typeof var3 === "string" && var3.length; // string num = typeof param1 === "string" && param1.length; // string })(param) : void
>((param1: string | number) => { // global vars in function declaration num = typeof var1 === "string" && var1.length; // string // variables from outer function declaration num = typeof var2 === "string" && var2.length; // string // parameters in outer declaration num = typeof param === "string" && param.length; // string // local var var3: string | number; num = typeof var3 === "string" && var3.length; // string num = typeof param1 === "string" && param1.length; // string }) : (param1: string | number) => void
>(param1: string | number) => { // global vars in function declaration num = typeof var1 === "string" && var1.length; // string // variables from outer function declaration num = typeof var2 === "string" && var2.length; // string // parameters in outer declaration num = typeof param === "string" && param.length; // string // local var var3: string | number; num = typeof var3 === "string" && var3.length; // string num = typeof param1 === "string" && param1.length; // string } : (param1: string | number) => void
>param1 : string | number
// global vars in function declaration
num = typeof var1 === "string" && var1.length; // string
>num = typeof var1 === "string" && var1.length : number
>num : number
>typeof var1 === "string" && var1.length : number
>typeof var1 === "string" : boolean
>typeof var1 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var1 : string | number
>"string" : "string"
>var1.length : number
>var1 : string
>length : number
// variables from outer function declaration
num = typeof var2 === "string" && var2.length; // string
>num = typeof var2 === "string" && var2.length : number
>num : number
>typeof var2 === "string" && var2.length : number
>typeof var2 === "string" : boolean
>typeof var2 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var2 : string | number
>"string" : "string"
>var2.length : number
>var2 : string
>length : number
// parameters in outer declaration
num = typeof param === "string" && param.length; // string
>num = typeof param === "string" && param.length : number
>num : number
>typeof param === "string" && param.length : number
>typeof param === "string" : boolean
>typeof param : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>param : string | number
>"string" : "string"
>param.length : number
>param : string
>length : number
// local
var var3: string | number;
>var3 : string | number
num = typeof var3 === "string" && var3.length; // string
>num = typeof var3 === "string" && var3.length : number
>num : number
>typeof var3 === "string" && var3.length : number
>typeof var3 === "string" : boolean
>typeof var3 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>var3 : string | number
>"string" : "string"
>var3.length : number
>var3 : string
>length : number
num = typeof param1 === "string" && param1.length; // string
>num = typeof param1 === "string" && param1.length : number
>num : number
>typeof param1 === "string" && param1.length : number
>typeof param1 === "string" : boolean
>typeof param1 : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>param1 : string | number
>"string" : "string"
>param1.length : number
>param1 : string
>length : number
})(param);
>param : string | number
}
// Return type of function
// Inside function declaration
var strOrNum: string | number;
>strOrNum : string | number
function f4() {
>f4 : () => string | number
var var2: string | number = strOrNum;
>var2 : string | number
>strOrNum : string | number
return var2;
>var2 : string | number
}
strOrNum = typeof f4() === "string" && f4(); // string | number
>strOrNum = typeof f4() === "string" && f4() : string | number
>strOrNum : string | number
>typeof f4() === "string" && f4() : string | number
>typeof f4() === "string" : boolean
>typeof f4() : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>f4() : string | number
>f4 : () => string | number
>"string" : "string"
>f4() : string | number
>f4 : () => string | number
|
