Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Mark Lawrence <breamoreboy@yahoo.co.uk>
Newsgroups: comp.lang.python
Subject: Re: Checking function's parameters (type, value) or not ?
Date: Wed, 6 Apr 2016 14:29:02 +0100
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Xref: csiph.com comp.lang.python:106575

On 06/04/2016 14:07, ast wrote:
> Hello
>
> I would like to know if it is advised or not to test
> a function's parameters before running it, e.g
> for functions stored on a public library ?
>
> Example:
>
> def to_base(nber, base=16, use_af=True, sep=''):
>
>     assert isinstance(nber, int) and nber >= 0
>     assert isinstance(base, int) and base >= 2
>     assert isinstance(use_af, bool)
>     assert isinstance(sep, str) and len(sep) == 1
>
>    tbc
>
> With these tests, you are sure that the function to_base is
> well used. But it slows down the program.
> Without, python interpreter may crash later in the function
> or worse provide a meaningless result.
>
> What library designers do ?
>


Please see 
http://ftp.dev411.com/t/python/python-list/13bhcknhan/when-to-use-assert

-- 
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence