[Python-Dev] Int FutureWarnings and other 2.4 TODOs (original) (raw)

Aahz aahz at pythoncraft.com
Mon Dec 1 20:00:23 EST 2003

On Sat, Nov 29, 2003, Guido van Rossum wrote:

(2) PEP 237 promises that repr() of a long should no longer show a trailing 'L'. This is not yet implemented (i.e., repr() of a long still has a trailing 'L'). First, past experience suggests that quite a bit of end user code will break, and it may easily break silently: there used to be code that did str(x)[:-1] (knowing x was a long) to strip the 'L', which broke when str() of a long no longer returned a trailing 'L'. Apparently some of this code was "fixed" by changing str() into repr(), and this code will now break again. Second, I like seeing a trailing L on longs, especially when there's no reason for it to be a long: if some expression returns 1L, I know something fishy may have gone on.

That makes sense to me; there should be an easy way from Python to detect what kind of object you've got (as a string representation), and repr() is precisely the place for it.

Aahz (aahz at pythoncraft.com) <*> http://www.pythoncraft.com/

Weinberg's Second Law: If builders built buildings the way programmers wrote programs, then the first woodpecker that came along would destroy civilization.

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