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copied!<p>There is an exceedingly nice method for performing recursion in language constructs that don't explicitly support recursion called a <em>fixed point combinator</em>. The most well known is the <a href="http://en.wikipedia.org/wiki/Fixed_point_combinator" rel="nofollow noreferrer">Y-Combinator</a>.</p> <p><a href="http://www.cs.cityu.edu.hk/~hwchun/31337/blog/2005/09/y-combinator-in-javascript.php" rel="nofollow noreferrer">Here is the Y combinator for a function of one parameter in Javascript</a>:</p> <pre><code>function Y(le, a) { return function (f) { return f(f); }(function (f) { return le(function (x) { return f(f)(x); }, a); }); } </code></pre> <p>This looks a little scary but you only have to write that once. Using it is actually pretty simple. Basically, you take your original lambda of one parameter, and you turn it into a new function of two parameters - the first parameter is now the actual lambda expression that you can do the recursive call on, the second parameter is the original first parameter (<code>point</code>) that you want to use.</p> <p>This is how you might use it in your example. Note that I am using <code>mapstrings</code> as a list of strings to look up and the pop function would destructively remove an element from the head.</p> <pre><code>geocoder.getLatLng(pop(mapstrings), Y( function(getLatLongCallback, point) { if (!point) { if (length(mapstrings) > 0) geocoder.getLatLng(pop(mapstrings), getLatLongCallback); return; } map.setCenter(point, 13); map.setZoom(7); map.addOverlay(new GMarker(point)); }); </code></pre>

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