RWC: All Unique

all-unique.js

/**
 * Determines whether all characters in a string are unique.
 * 
 * Original question:
 * **Write a function that determines if all the characters in a given string are unique.**
 * Can you do this without making any new variables? You choose if you want to include
 * capitalization in your consideration for this one, as a fun challenge.
 * 
 * @param {string} str string to test
 * @param {boolean} [caseSensitive] whether to take capitalization into account
 * @returns {boolean} whether all characters in the string are unique
 */
function allUnique(str, caseSensitive = true) {
	return caseSensitive ?
		new Set(str.split('')).size === str.length :
		new Set(str.toLowerCase().split('')).size === str.length;
}

console.log(allUnique('Cassidy'));		// false
console.log(allUnique('cat & dog'));	// false
console.log(allUnique('cat+dog'));		// true

console.log(allUnique('Cc'));			// true
console.log(allUnique('Cc', false));	// false

Nice 🙂