Re: [StGit PATCH] Parse commit object header correctly

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 9, 2012, 03:58 UTC
Message-ID: <7v39akzmgx.fsf@alter.siamese.dyndns.org>
In-Reply-To: <op.v9dl1e0v0aolir@keputer.lokaal>

"Frans Klaver" <fransklaver@gmail.com> writes:

Show 16 quoted lines

>>>>           for line in lines:
>>>>               try:
>>>>                   key, value = line.rstrip('\n').split(' ', 1)
>>>>               except ValueError:
>>>>                   continue
>>>
>>> This is generally considered more pythonic: "It's easier to ask for
>>> forgiveness than to get permission".
>>
>> Given that Junio explicitly wanted to allow lines with no spaces, I
>> assume that lack of a space is not an error but rather a conceivable
>> future extension.  If my assumption is correct, then it is misleading
>> (and inefficient) to handle it via an exception.
>
> I find the documenting more convincing than the efficiency, but from
> the phrasing I think you do too.

A line that consists entirely of non-SP may or may not a conceivable future extension, but the point is to "skip without barfing anything you do not understand".

I wouldn't oppose the rewrite that uses try/except ValueError if "everything in this try block will parse what I understand correctly, and any ValueError exception this try block throws is an indication that I encountered what I do not understand and I must skip" is the more pythonic way to express that principle. Python is not my primary language as I said, and in addition StGit may have its own style I haven't learned.