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POJavascript - Set variable value inside function
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copied!<p>I'd like to declare some variables, an then let let a function build the actual objects and assign their reference to these previously declared variables.</p> <p>The way I do it now works, but it gets tedious with many variables.</p> <pre><code>function bar(obj) { var newObject = {'an':'object'}; obj['element'] = newObject; } function foo() { var ref={}; bar(ref); ref=ref.element; // Tedious line } </code></pre> <p>For those wondering why I would like to do such a thing, I built a simple function to generate the DOM from JSON. It goes something like that, with <code>#bind</code> used to do what <code>bar</code> does in the previous snippet :</p> <pre><code>var legend = {}; $('#element').append(['form',['fieldset', ['legend',{'#bind':legend},['text':'Legend title']] ]].getDomForThis()); legend=legend.element; </code></pre> <p>Now I can append some new elements after the legend with something like</p> <pre><code>for(fieldName in fields) { legend.insertAfter(['div',[['input',['name':fieldName]],...]].getDomForThis()); } </code></pre> <p>I'd like to avoid having to write the tedious line. It's like <code>createElement</code> and <code>appendChild</code>, one function call should be enough !</p> <p><strong>UPDATE</strong> : After some thought, I believe there is no way to do that with Javascript. I was hoping for some hidden Javascript magic somewhere, but I have reason to think it will not happen.</p> <p>Basically, I'd like to assign to a variable reference a new value, without creating a new reference. But a function argument <code>a</code> is distinct from the variable <code>v</code> it represents. The object pointed at are the same, but the adress of the two variables are different. Hence, assigning a new value to <code>a</code> cannot change the value of <code>v</code> in any way.</p> <p>In other words, every variable has its own address, and there's not any other way to change what it points at, than referencing it explictly.</p> <p>And in my case, because <code>ref</code> is "private" to the function, there's no way to access it from somewhere else.</p> <p>Too bad...</p>

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