[Python-Dev] For review: PEP 285: Adding a bool type (original) (raw)

Guido van Rossum guido@python.org
Fri, 08 Mar 2002 14:41:28 -0500

The effort required to do this is not the argument, it's the fact that you are trying to break working code without any real life need. The PEP doesn't mention a single example where the advantage is so obvious that it requires breaking code.

OK, now we're talking. You want more motivation. See my response to David Ascher; I'm going to add all that to the PEP online too.

> > I'd be happy with repr(True) giving me 'True', > > but not str(True). > > It just seems to make more sense if booleans print as True and False. > But if that really is going to be the only place where things break, > I'm willing to reconsider this.

Good.

This is now in the PEP as an option.

The problem is that the boolean output may not have been intended by the programmer. All he ever got was the integers 1 and 0 -- it was never obvious to the pure Python programmer that these two values were acutally the singletons PyTrue and PyFalse. Now you want to add additional semantics to those and things will look different on output.

In the long run, you'll thank me for this.

--Guido van Rossum (home page: http://www.python.org/~guido/)