Replace

Disclosure

Most of the problems under my TypeHero Challenges folder were either obtained from typehero.dev or from type-challenges repo. Purpose of these articles are just to document my approaches for my easy reference. Please visit the respective links for more info.

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Problem Description

Implement Replace<S, From, To> which replace the string From with To once in the given string S

For example:

type replaced = Replace<'types are fun!', 'fun', 'awesome'> // expected to be 'types are awesome!'

Solutions

Approach: Using infer and Exclude

type Replace<S extends string, From extends string, To extends string> = 
	S extends `${infer Prefix}${Exclude<From, ''>}${infer Suffix}`
		? `${Prefix}${To}${Suffix}`
		: S;