# File format.rb, line 472
    def changeVarValue (var_value, var_name, aBinding)
      result = var_value[0, @len]
      max_space = var_value[0,@len + 1].rindex(' ')
      if (var_value.length <= @len)
        result = var_value
        max_space = @len
      end
      if (max_space != nil)
        result = var_value[0,max_space]
      end
      setVarValue( var_name, var_value[result.size(),var_value.size()],
                  aBinding)
      return result
    end