title: Why is there no clamp function in math.h
body: <p><code>math.h</code> goes to the trouble of providing <code>min</code> and <code>max</code>, but not a clamp function. I would have thought that as they are all usually similar implementation-wise they would all appear in the same library.</p>
  
  <p>Is there any particular reason that <code>math.h</code> does not feature a clamp function|macro? 
  Is it that the creators of <code>math.h</code> did not deem it necessary or did they just not think about it?</p>
  
  <p>EDIT:
  It seems people are missing the point here. I'm not asking why didn't they add clamp because I'm lazy and don't like writing a new clamp - quite the opposite, I hardly ever use it (though admittedly I use it more than I use some of the standard libraries).</p>
  
  <p>What I'm asking is "does anyone know of any reason why the c++ standardisation authorities or creators or whoever chose not to include a clamp function in <code>math.h</code>?".</p>
  
  <p>I am by no means complaining that it is not in <code>math.h</code>, I am merely asking "is there a good reason it isn't there?".</p>
  
  <p>EDIT:
  I am <em>explicitly</em> <strong>not</strong> asking how to write a <code>clamp()</code> function.</p>