title: Evaluate C# expression inside another expression
body: <p>I want to use an expression in another one:</p>
  
  <pre><code>Expression&lt;Func&lt;double, double&gt;&gt; f = x =&gt; x * x * 27 + blah ... expression with x;
  
  Expression&lt;Func&lt;double, double&gt;&gt; g = y =&gt; 3 + 8 * f.Compile()(y) * y * blah... expression with y and f(y);
  </code></pre>
  
  <p>This will not work when sent to LINQ to SQL because f.Compile() is unknown to SQL.</p>
  
  <p>How do you evaluate the expression <code>f</code> on the variable <code>y</code> without compiling it, but still using normal syntax to define <code>g</code>?</p>
  
  <p>I don't want to have to define all of <code>g</code> with some unreadable <code>Expression.Add</code>/<code>Expression.Multiply</code> etc. statements.</p>
  
  <p>Thanks.</p>