Re: [PATCH nd/attr-match-optim-more 2/2] attr: more matching optimizations from .gitignore

> Johannes Sixt <j.sixt@viscovery.net> writes:
>
>> Am 10/9/2012 7:08, schrieb Junio C Hamano:
>>> Imagine if we allowed only one attribute per line, instead of
>>> multiple attributes on one line.
>>>     
>>>  - If you want to unset the attribute, you would write "path -attr".
>>> 
>>>  - If you want to reset the attribute to unspecified, you would
>>>    write "path !attr".
>>> 
>>> Both are used in conjunction with some other (typically more
>>> generic) pattern that sets, sets to a value, and/or unsets the
>>> attribute, to countermand its effect.
>>> 
>>> If you were to allow "!path attr", what does it mean?  It obviously
>>> is not about setting the attr to true or to a string value, but is
>>> it countermanding an earlier set and telling us to unset the attr,
>>> or make the attr unspecified?
>>
>> If I have at the toplevel:
>>
>>   *.txt  whitespace=tabwidth=4
>>
>> and in a subdirectory
>>
>>   *.txt  whitespace=tabwidth=8
>>   !README.txt
>>
>> it could be interpreted as "do not apply *.txt to REAME.txt in this
>> subdirectory". That is, it does not countermand some _particular_
>> attribute setting, but says "use the attributes collected elsewhere".
>
> It makes it unclear what "elsewhere" means, though (besides, it does
> not match the way the matching logic works at all).