Type of regular expression
aahz at pythoncraft.com
Tue Jul 6 15:55:41 CEST 2004
In article <4ywu1mu8nu.fsf at skjellgran.ii.uib.no>,
Joakim Hove <hove at bccs.no> wrote:
>Thanks for answering, however I am afraid i posed the question
>somewhat ambigously: The point is that i want the function to do
>different things depending on the type of input:
> if type(arg) is RegexpType:
> # Handle regular expression argument
> elsif type(arg) is StringType:
> # Handle string argument - which is something
> # completely different.
> sys.exit("Wrong argument type")
That's a Bad Idea. What if someone gives you a Unicode string?
Generally speaking, type-based dispatch will run into problems sooner or
later. The better approach: you have to know at some point what kind of
data is being passed around -- when you create a target (usually a name)
for it. If you really need to know the type later on, create a
container that includes the necessary type information.
Aahz (aahz at pythoncraft.com) <*> http://www.pythoncraft.com/
"Typing is cheap. Thinking is expensive." --Roy Smith, c.l.py
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