[Tutor] OK, dumb question

[David Ascher]

On Mon, 7 Jun 1999, K P wrote:

> I seem to be stuck on the littlest of problems, how do I do this in Python:
> 	iterate through a 'list' (term used loosely) of twelve class variables,
> check each for changes

> class Meat:
>    def __init__(self, colour, type):
>       self.colour = colour
>       self.type = type
>       self.flavor = ' '
> 
> class Spam:
>    def __init__(self):
>       self.beef = Meat('red', 'beef')
>       self.chicken = Meat('white', 'fowl')
>    def quality(self):
>       #In this function I would check the type and colour versus a 'chart'
> (probably a dictionary look-up)
>       #e.g. if self.beef.colour = 'red' and self.beef.type = 'beef'
> then self.beef.flavor = 'good'
>       #In my 'real' script I would be testing 12-20 class member variables
> against a small set of immutable variables
>       #what would be the simplest/fastest/most effective way to code that
> in python?

Use getattr()/setattr(), as in:

class Spam:

  ingredient_list = ['beef', 'chicken']

  #...

  def quality(self):
    for ingredient_name in self.ingredient_list:
      ingredient = getattr(self, ingredient_name)
      colour = getattr(ingredient, 'colour')
      type = getattr(ingredient, 'beef')
      if colour == 'red' and type == 'beef':
        ingredient.flavor = 'good'
        # or setattr(ingredient, 'flavor', 'good')

Hope this helps.

--david ascher