code: private RValue executeVariableAccess(Expr.VariableAccess expr, CallStack frame) {
  		Decl.Variable decl = expr.getVariableDeclaration();
  		return frame.getLocal(decl.getName());
  	}
docs: Execute a variable access expression at a given point in the function or
  method body. This simply loads the value of the given variable from the
  frame.
  
  @param expr
  --- The expression to execute
  @param frame
  --- The current stack frame
  @return