prepending a variable in javascript

Is there a function out there that will do this:

somevar="something"+somevar;

such as .prepend()? if there isnt, how would imake this function work like this:

somevar.prepend(),

NOT like this though:

prepend(somevar, prepend_value);


If possible, I want both answers so if i ever need to i can alter variables with functions without putting the variable i want to alter in the argument list.
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OscurochuAsked:
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ahoffmannCommented:
see JavaScripts prototype syntax and JSON http://www.json.org/
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stanscott2Commented:
Check out the use of the EVAL function.  This function takes a string and executes it, which I believe is what you're looking for.
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BadotzCommented:
Why over-complicate things? What would this function gain you?

Obviously you know the value to prepend; why not just do as you suggested:

somevar="something"+somevar;
0
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OscurochuAuthor Commented:
using a function to prepend a variable will clear up a lot of code. i like to keep my code clean, so:


document.getElementById('blah').innerHTML="blah blah"+document.getElementById('blah').innerHTML


makes the code look cluttered. it would be easier to just use:

document.getElementById('blah').innerHTML.prepend('blah blah');
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stanscott2Commented:
In the example you just gave, you really want to insert HTML, so use this function with two argument, the node to be acted on, and the text to be added:

prepend('myNode','blah blah');

function prepend(nd, txt) {
     var curNode = document.getElementById(nd);
     curNode.insertBefore(document.createTextNode(txt),curNode.firstChild);
}

If you aren't sure that there will always be a firstChild node, then modify the function like this:

function prepend(nd, txt) {
     var curNode = document.getElementById(nd);
     if (curNode.firstChild) {
          curNode.insertBefore(document.createTextNode(txt),curNode.firstChild);
     } else {
          curNode.appendChild(document.createTextNode(txt));
     }
}
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OscurochuAuthor Commented:
i already said, i donot want it to work like that because of specific reasons i cant remember right at this moment. im trying to get it to work  like this, if possible:

document.getElementById('blah').innerHTML.prepend('some text');

innerHTML is just an example. if the above function is not possible, then i will just write a function that will use two arguments to do the work.
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ahoffmannCommented:
as I already said: JSON can do that
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BadotzCommented:
<$.02>Much ado about nothing</$.02>
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OscurochuAuthor Commented:
i dont understand how JSON works, can you help me out with that?
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ahoffmannCommented:
see prototype.js, something like:

String.extend(String.prototype, {prepend: function(str){ /* work here */ });

€.02 as asked for ;-)
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