[Bf-python] Re: [Bf-blender-cvs] CVS commit: blender/source/blender/include BDR_editcurve.h BIF_editarmature.h BIF_meshtools.h blender/source/blender/python/api2_2x Object.c blender/source/blender/python/api2_2x/doc Object.py blender/source/blender/src editarmature.c editcurve.c meshtools.c

Toni Alatalo antont at kyperjokki.fi
Tue Jan 3 05:38:20 CET 2006


On Tuesday 03 January 2006 04:35, Campbell Barton wrote:
>   Made respective join_* functions return 0 if the join was not mode, 1
> when it workes.
> -73   blender/source/blender/python/api2_2x/Object.c

	@return: 0 is returned if the join is not successfull, otherwise 1 will be 
returned.

i object this, and prefer failing operations to raise exceptions.

there are some parts in the bpy api that dont, so arguably that addition is 
consistent with some existing things. but i hope inconsistent with even more 
of bpy, and i think with all of normal py .. or?

is there some other reason for returning a value upon failure, like being 
afraid of causing unhandled exceptions in scripts?

i suggest (again) we always adhere to the 'samurai principle' like normally in 
Python  http://c2.com/cgi/wiki?SamuraiPrinciple
 
have had painful experiences in bpy scripting when .. ah, now i see this case 
is not that bad: the pain is in cases where in normal case an object to be 
worked on later is expected, but e.g. a None is gotten instead. this is the 
case with 
http://www.blender.org/documentation/240PythonDoc/Ipo.Ipo-class.html#getCurve 
which Returns: the corresponding IpoCurve, or None. 

that can hide bugs, be nasty.

perhaps this joining too?

like when you have code where join, assume it always succeeds, and then 
operate on the objects later .. and get weird results, or a strange bug in 
later code, and dont see that it was the join that failed and not some later 
operation / your general logic / .. disclaimer: i dont know when joining can 
fail.

sorry for the long messy post, must get more sleep now, but i hope the point 
got thru.

and thanks for all this great work, i hope you dont mind us all being such 
asses! :)

~Toni



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