(Moved from rom microsoft/TypeScript-DOM-lib-generator#1562)
I am using TypeScript 5.0.4.
I have noticed the typing of String.replace seem oddly convoluted.
From lib.es5.d.ts:
interface String {
replace(searchValue: string | RegExp, replaceValue: string): string;
replace(searchValue: string | RegExp, replacer: (substring: string, ...args: any[]) => string): string;
}From lib.es2015.symbol.wellknown.d.ts:
interface String {
replace(searchValue: { [Symbol.replace](string: string, replaceValue: string): string; }, replaceValue: string): string;
replace(searchValue: { [Symbol.replace](string: string, replacer: (substring: string, ...args: any[]) => string): string; }, replacer: (substring: string, ...args: any[]) => string): string;
}Like the first parameter is declared as an union, I would expect the second to be the same, at least in the lib.es5 version.
Notably, this makes the following code not compile:
// The second argument is an union of replaceValue and replacer from lib.es5
const replacementSteps: ([RegExp, string | ((substring: string, ...args: any[]) => string)])[] = [
[/(a|b)/gi, "a"],
[/(c|d)/gi, match => match.toUpperCase()],
];
let myString = "abcdef";
for (const [searchValue, replacement] of replacementSteps)
myString = myString.replace(searchValue, replacement); // TS2345 - the second parameter is considered invalidBy adding this into my declaration, the code works:
declare interface String {
replace(searchValue: string | RegExp, replaceValue: string | ((substring: string, ...args: any[]) => string)): string;
}I cannot propose a solution other than my last hack, and of course the variants with Symbol would have to be taken into account. Please consider this just a note.
See also this: #54223
(Moved from rom microsoft/TypeScript-DOM-lib-generator#1562)
I am using TypeScript 5.0.4.
I have noticed the typing of
String.replaceseem oddly convoluted.From
lib.es5.d.ts:From
lib.es2015.symbol.wellknown.d.ts:Like the first parameter is declared as an union, I would expect the second to be the same, at least in the
lib.es5version.Notably, this makes the following code not compile:
By adding this into my declaration, the code works:
I cannot propose a solution other than my last hack, and of course the variants with
Symbolwould have to be taken into account. Please consider this just a note.See also this: #54223