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Check if a string is lower case

Written byPhuoc Nguyen
Created
19 Apr, 2020
Last updated
13 Oct, 2021
Category
Validator
JavaScript version
isLowerCase.js
const isLowerCase = (str) => str === str.toLowerCase();
TypeScript version
isLowerCase.ts
const isLowerCase = (str: string): boolean => str === str.toLowerCase();

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