NAME

Math::Expr::Var - Represents a agebraic rule 

SYNOPSIS

  reuire Math::Expr::Var;
  reuire Math::Expr;
	
	$r=new Math::Expr::Var($from, $to);
  @res=$r->Apply($expr)

DESCRIPTION

This will create a rule that converts the expression $from to $to,
and then apply that rule to $expr. $from, $to, $expr are all
Math::Expr::Opp structures that should be Simplified to work ok.

The result is a array @res of Math::Expr::Opp objects which should 
contain the results of applying the rule once on $expr in all 
possible ways. They are all simplified, and duplicaions are removed.

METHODS

$r=new Math::Expr::Var($from, $to);

Makes a rule converting the Math::Expr::Opp structur $from into $to.