title: Function pointer parameter without asterisk
body: <p>I have seen this definition of a function that receives a function pointer as parameter:</p>
  
  <pre><code>double fin_diff(double f(double), double x, double h  = 0.01) {
    return (f(x+h)-f(x)) / h;
  }
  </code></pre>
  
  <p>I am used to see this definition with an asterisk, i.e.:</p>
  
  <pre><code>double fin_diff(double (*f)(double), double x, double h  = 0.01);
  </code></pre>
  
  <p>Do you know why the first definition is also valid?</p>