basic class question..

Pyrot sungsuha at gmail.com
Mon Nov 16 01:26:59 CET 2009


On 11월15일, 오후9시52분, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Pyrot schrieb:
>
> > class rawDNA:
> >    import string
>
> Importing here is unusual. Unless you have good reasons to do so, I
> suggest you put the imports on top of the file.
>
> >    trans = string.maketrans("GATC","CTAG")
>
> >    def __init__(self, template = "GATTACA"):
> >            self.template = template  //shouldn't this make "template"
> > accessible within the scope of "rawDNA"??
>
> No.
>
>
>
> >    def noncoding(self):
> >            print template.translate(trans)  //
>
> This needs to be
>
>    print self.template.translate(trans)
>
> Thes scopes insied a class are only the method-locals (to which the
> parameters count of course), and globals.
>
> Diez

Thanks for the tip Diez.

(Tthe core reason that I'm bothering with this at all is because I
heard imports are costly(in time, space, processing power). If this
turns out to be a non-issue, than my questions regarding Imports are
all moot :->)

I forgot to write about my second question which was:

what happens when I use the import statement within a class/function
declaration?
I'm thinking either
1) It imports during the class/function declaration
2) It imports the first time a class/function call(x = rawDNA() )
occurs

But if it's 2) then is the import valid outside of the function/class?
what happens when the last function reference is removed?(del x)

obviously this is a lot of questions...

I respect your(or anyone who would like to help me) time, so all I ask
is some kind of document or "Best practices" guide dealing all about
"import".(because sadly, http://docs.python.org/reference/simple_stmts.html#the-import-statement
does not ask my questions)




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