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Package detail

is-lower

redyetidev8MIT1.0.1

Check whether a string is lowercase

is, string, lowercase, is-lower

readme

is-lower (v1.0.1)

A simple utility to determine if a given string is in lowercase.

Installation

You can install is-lower using npm:

npm install is-lower

Usage

To use is-lower, require it in your application and call it with the string you want to check. The function will return true if the string is entirely in lowercase, and false otherwise.

const isLowerCase = require('is-lower');

console.log(isLowerCase("Hello"));       // false
console.log(isLowerCase("one"));         // true
console.log(isLowerCase("javascript"));  // true
console.log(isLowerCase("NODEJS"));      // false
console.log(isLowerCase("2024"));        // true
console.log(isLowerCase("hello world")); // true
console.log(isLowerCase("Hello World")); // false
console.log(isLowerCase("hello123"));    // true
console.log(isLowerCase("!@#$%"));       // true
console.log(isLowerCase("h3ll0"));       // true
console.log(isLowerCase(""));            // true (an empty string is considered lowercase)

// It can handle overrides
String.prototype.toLowerCase = () => false;
console.log(isLowerCase("hello world")); // true
console.log(isLowerCase("Hello World")); // false

// And non-strings
console.log(isLowerCase({})); // false
console.log(isLowerCase(-1)); // false