Is it possible to write the following logical constrain in linear programming? 

Let $v$ be an integer variable and $k$ an integer constant. Let $y$ be a binary variable. The logical constrain requires:

$y=1 \Longleftrightarrow v=k$

I need this kind of contrain in linear programming to use it in AMPL, but I really can't find a way to write it down as a linear constrain. 

Thanks to who'll help me!