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copied!<p>You can use the <code>let</code> syntax in your code:</p> <pre><code>string test = "12,23,34,23,12"; var res = from string s in test.Split(',') let u = s+s select int.Parse(u); </code></pre> <p>Alternately, you could use the LINQ extension methods directly instead of the special syntax:</p> <pre><code>string test = "12,23,34,23,12"; var res = test.Split(',') .Select(s => { var u = s + s; return int.Parse(u); }); </code></pre> <p><strong>Since the question was updated:</strong></p> <p>I don't mean to be disrespectful, but I think this solution isn't necessary.</p> <p>Here's a bit of an exploration: </p> <p>If we want to accept truly "arbitrary" lambdas like you say, then they can come from an outside source, and <code>Wrap</code> does nothing because it's the same as <code>f()</code>:</p> <pre><code>// with 'f' as some arbitrary lambda, then this: var res = from string s in test.Split(',') select f.Wrap(); // is the same as: var res = from string s in test.Split(',') select f(); </code></pre> <p>But if you do this, <code>f</code> can't depend upon <code>s</code> in any way (for example, this way you can't write your example code):</p> <pre><code>// e.g. where does s come from? var f = () => { var u = s+s; return int.Parse(u); }; // we can write it like this, as a function of 's': var f2 = s => { var u = s+s; return int.Parse(u); }; //but then you can just use "select f2(s)" and we're back not needing Wrap any more </code></pre> <p>What we're really looking for is arbitrary closures over <code>s</code>. For this to happen, the lambdas have to be defined inline, where <code>s</code> is in scope, so you aren't really accepting truly "arbitrary" lambdas any more, and they have to be written directly in the code.</p> <p>This is why I proposed the <code>let</code> syntax, since any lambda you can come up with can be converted to that syntax, and it goes with the rest of the query syntax. This is what <code>let</code> is designed for! :)</p> <p>Alternately, you could just use lambdas which take parameters like <code>f2</code> above.</p> <p>If you really want to stick with the lambda syntax, I'd suggest using the extension methods. Like I said in my comment, it looks like you're looking for something halfway between query & extension syntax.</p> <p>I'd be interested in why you want to use the lambda syntax with the query syntax? </p> <p>Hope this helps :)</p>

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