30-seconds-of-code/snippets/isUpperCase.md

isUpperCase

Checks if a string is upper case.

Convert the given string to upper case, using String.toUpperCase() and compare it to the original.

const isUpperCase = str => str === str.toUpperCase();

isUpperCase('ABC'); // true
isLowerCase('A3@$'); // true
isLowerCase('aB4'); // false