title: implementing JMP in flex
body: <p>My task is to implement interpreter of assembly-like language using Flex.</p>
  
  <p>There are such commands as:</p>
  
  <blockquote>
    <p>add x y z, (z = x + y)</p>
    
    <p>sub x y z, (z = x - y)</p>
    
    <p>mul x y z, (z = x * y)</p>
    
    <p>div x y z, (z = x / y)</p>
    
    <p>let x 10, (x = 10)</p>
    
    <p>mov x y, (y = x)</p>
  </blockquote>
  
  <p>Implementing interpreter of this commands is pretty easy using Flex. </p>
  
  <p>I have stuck with implementing <code>JMP line, (current line = line)</code> instruction. I have no idea how to reset Flex current parsing line or something like that.</p>