[Bf-python] Thought about IRC meeting and beyond

[Stephen Swaney]

On Mon, Jan 09, 2006 at 01:45:28PM -0500, Joseph Gilbert wrote:
> 
> 
> Toni Alatalo wrote:
> 
> >On Monday 09 January 2006 16:31, Willian Padovani Germano wrote:
> > 
> >
> >>>1) The use of True/False over 1/0:
> >>>     
> >>>
> >>Hi Joseph. Python itself accepts many things as true or false, as
> >>discussed previously, but of course we won't go there (we won't accept
> >>"" as false for functions that don't even expect a string, etc).
> >>   
> >>
> >
> >err, anything that can be evaluated as true/false should accepted where a 
> >boolean is expected. those arguments should not be typechecked, just use 
> >that eval func that python provides. why not just do what python does?
> > 
> >
> 
> Again I feel that PyObject_IsTrue is too liberal for use with tp_getset. 
> However I may be (other than theeth) the only person to feel that 
> 'wassup' != True.

Allow me to disagree based on two principles:
1) Python itself is very flexible when evaluating true/false.
2) Be flexible in what you accept, be strict in what you output.

At the very least we need to accept 1/0 and True/False for our boolean
vars.  Since we need to test for either case and Python provides the
lovely convenience func PyObject_IsTrue, I recommend we go all the way
ad use it.

The rationale for this is similar in what the C++ compiler does when trying
to match method signatures where it will run appropriate (and often surprising)
converters to make things work out nicely

If we are going to be strict about bools, we are essentially requiring
the scripter to write
  A.bool_var = bool( some_data )
rather than simply accepting
  A.bool_var = some_data

I think we should be nice and run the converter for them.  Expecially
since we don't have to write it!  (there is another systems integration
principle for you: write as little code as possible)

For return values, booleans should return bools and not 1/0.

-- 
Stephen Swaney			
sswaney at centurytel.net