Some basic newbie questions...

[Grant Edwards]

On 2006-12-28, jonathan.beckett <jonathan.beckett at gmail.com> wrote:
> Hi all,
>
> While working on support at work, I have been picking away at Python -
> because I think it could be a valuable scripting tool for building
> utilities from. I have been reading the python.org tutorials, and
> playing around with some basic code, but I have ended up with a few
> questions that probably have straightforward answers - any quick
> explanations or assistance would be fantastic...
>
>
> Question 1...
> Given the code below, why does the count method return what it does?
> How *should* you call the count method?
>   a = []
>   a.append(1)
>   print a.count

a.count(1)
a.count(2)

> Question 2...
> What is the correct way of looping through a list object in a class via
> a method of it? (I've hit all sorts of errors picking away at this, and
> none of the tutorials I've found so far cover it very well) - apologies
> for the arbitrary class - it's the first example I thought up...
>
> class Gun:
>     Shells = 10

What you wrote created a class variable: there's only a single
"Shells" object and it's shared by all instances of the class.
Based on the way you're using it, I presume you want each gun
to have it's own Shells value. You probably want something like
this:

class Gun:
    def __init__(self):
       self.Shells = 10    
       
> class Battleship:
>     Gun1 = Gun()
>     Gun2 = Gun()
>     Guns = [Gun1,Gun2]
>
>     def getShellsLeft(self):
>         NumShells = 0
>         for aGun in Guns:
>             NumShells = NumShells + aGun.Shells
>         return NumShells
>
> Bizmark = Battleship()
>
> print Bizmark.getShellsLeft()
>
>
> In the above code, I guess I'm just asking for the *correct* way to do
> these simple kinds of things...


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