__getitem__?

[Emile van Sebille]

Hi Joshua,

First, start using spaces instead of tabs when you post.  It makes it easier
as we won't need to reconstruct your intent.

Anyway, break it down:

a[0][0] = 1

getitem is returning the asked for element a[0], and then you are assigning
to the [0] part of it.

HTH,

--

Emile van Sebille
emile at fenx.com

---------
"Joshua Tompkins" <joshua at bladeagency.com> wrote in message
news:fcc1f856.0108240724.1e884737 at posting.google.com...
> Hi.
>
> As sort of an experiment, I'm implementing a multi-dimensional list
> object in python (I'm not at sure that there's any real value in this,
> as there's probably already stuff like it out there, but hey, I'm
> bored).  Here's the code (27 lines):
>
> class mdList:
> version = 0.15
>
> def __init__( self, xBound, yBound ):
> print "mdList version " + str( self.version )
> self.dataList = []
>
> self.xLength = xBound
> self.yLength = yBound
>
> i = 0
>
> while i < xBound:
> j = 0
> yList = []
>
> while j < yBound:
> yList.append( 0 )
> j += 1
>
> if len( yList ) > 0:
> self.dataList.append( yList )
> i += 1
> return None
>
> def __getitem__( self, key ):
> return self.dataList[key]
>
> My question is about the __getitem__ method.  After I added it, I
> could access the dataList internal variable like this (where a is the
> class instance):
>
> a[0][0]
>
> That's pretty neat (but is that how I should be doing it?  I don't
> understand how I can access the second array dimension when there's
> only one argument passed to the method), but here's the real question:
>  why does this (see below) work?
>
> a[0][0] = 1
>
> Thanks in advance,
>
> -joshua