JSFiddle - React, Tailwind, and code Playground

(SOPT) por quê o inArray não funciona?

HTML

<div id="txt1">não</div>
<br />
<div id="txt2">sim</div>
<br />
<div id="txt3">sim</div>

JavaScript

var titles = ['{EXTENSIONS}', '{dummy}'];

var title1 = "{EXTENSIONS}";
if (~$.inArray(title1, titles)) {
    $('#txt1').text('No!');
}

var title2 = "{extensions}";
if (~$.inArray(title2, titles)) {
    $('#txt2').text('Yes!');
}

var title3 = "{dummy}";
if (~$.inArray(title3, titles)) {
    $('#txt3').text('Yes!');
}

/*
	inArray: function( elem, array ) {
		if ( array.indexOf ) {
			return array.indexOf( elem );
		}

		for ( var i = 0, length = array.length; i < length; i++ ) {
			if ( array[ i ] === elem ) {
				return i;
			}
		}

		return -1;
	},
    */