Making class attributes non-case-sensitive?

Rafe rafesacks at gmail.com
Mon Oct 13 13:08:03 CEST 2008


Just so I don't hijack my own thread, the issue is 'how to wrap an
object which is not case sensitive'.

The reason I am stuck dealing with this?... The application's API is
accessed through COM, so I don't know if I can do anything but react
to what I get. The API was written while the app (Softimage|XSI - one
of 3 leading 3D applications for high-end visual effects) was owned by
Microsoft. I'm not sure if it is standard for Microsoft or just the
way this app was implemented (perhaps because under-users were
scripting in VBscript which is not case sensitive).

XSI allows many languages to be used via COM, even from within the
software (there are built-in code editors). In the early days,
VBScript was the most common scripting language used while anything
more hard-core was done in C++ (of course the C implementation is case
sensitive - well as far as I know). Then JScript became the most
common, now Python is considered standard.

Anyway, the standard practice is to use mixed-case, so I need to
adhere to it as the resulting framework I am creating needs to be
intuitive to use (my end-user is still writing code. It's an API for
an API I guess...)

I don't *think* I need to worry too much about performance because I'm
not doing any serious processing, this is more about convention
enforcement and quality control rather than number crunching. I might
try to write something generic which gets executed by the wrappers
__getattr__ and __setattr__, but I was hoping for some nifty
workaround, maybe in the form of a decorator or something? Again...
any ideas?


Cheers,

- Rafe


On Oct 13, 4:15 pm, "Diez B. Roggisch" <de... at nospam.web.de> wrote:
> Rafe wrote:
> > Hi,
>
> > I'm working within an application (making a lot of wrappers), but the
> > application is not case sensitive. For example, Typing obj.name,
> > obj.Name, or even object.naMe is all fine (as far as the app is
> > concerned). The problem is, If someone makes a typo, they may get an
> > unexpected error due accidentally calling the original attribute
> > instead of the wrapped version. Does anyone have a simple solution for
> > this?
>
> > I can protect against some cases just by making an 'alias':
> > class AClass(object):
> >     def name(self):
> >         print "hello"
>
> >     Name = name
>
> > ...but this doesn't protect against typos, it gets more complicated
> > with multi-word attribute names, and it makes my epydocs confusing to
> > read since all spelling versions are shown (I AM concerned about my
> > docs being clear, but not as much as stopping typo related errors).
>
> > I thought about using my wrapper's __getattr__ and __setattr__, but I
> > I am concerned about the overhead of every delegated attribute call
> > running a search and compare (<paramName>.lower() based compare?).
>
> > Any ideas or precedence?
>
> Ideas? Don't do that...
>
> Seriously: where does that code come from, who's typing it? If it is python,
> then make people follow python's rules. If it is some sort of homebrewn
> language you map to python, adapt the mapper to enforce lower-case and make
> all your properties lower case.
>
> Diez




More information about the Python-list mailing list