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POHow is a Javascript string not an object?
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  1. POHow is a Javascript string not an object?
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    copied!<p><em>It's not the setup to a joke, i'm really asking.</em></p> <p><a href="http://www.yuiblog.com/blog/2006/11/13/javascript-we-hardly-new-ya/" rel="noreferrer">Douglas Crockford is fond of saying</a> that in the javascript prototypal object-oriented language there is no need for <code>new</code>. </p> <p>He explains that <code>new</code> was simply added to give people coming from class-based (i.e. "<em>classical</em>") object oriented programming languages some level of comfort:</p> <blockquote> <h1><a href="http://www.yuiblog.com/blog/2006/11/13/javascript-we-hardly-new-ya/" rel="noreferrer">JavaScript, We Hardly <code>new</code> Ya</a></h1> <p>JavaScript is a prototypal language, but it has a <code>new</code> operator that tries to make it look sort of like a classical language. That tends to confuse programmers, leading to some problematic programming patterns.</p> <p>You never need to use <code>new Object()</code> in JavaScript. Use the object literal <code>{}</code> instead. </p> </blockquote> <p>Okay, fine: </p> <ul> <li><code>new</code> bad </li> <li><code>{}</code> good</li> </ul> <p>But then commenter <a href="http://www.yuiblog.com/blog/2006/11/13/javascript-we-hardly-new-ya/#comment-588504" rel="noreferrer">Vítor De Araújo pointed out that the two are not the same</a>. He gives an example showing that a <code>string</code> is not like an <code>object</code>:</p> <blockquote> <p>A string object and a string value are not the same thing:</p> <pre><code>js&gt; p = "Foo" Foo js&gt; p.weight = 42 42 js&gt; p.weight // Returns undefined js&gt; q = new String("Foo") Foo js&gt; q.weight = 42 42 js&gt; q.weight 42 </code></pre> <p>The string value cannot have new properties. The same thing is valid for other types.</p> </blockquote> <p>What is going on here that an <code>string</code> is not an <code>object</code>? Am i confusing javascript with some other languages, where everything is an object?</p>
 

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