On Jul 3 2007, 10:14, Guido van Rossum wrote: >On 6/30/07, Matt Chisholm <[EMAIL PROTECTED]> wrote: >>I've created and submitted a new PEP proposing support for labels in >>Python's break and continue statements. Georg Brandl has graciously >>added it to the PEP list as PEP 3136: >> >>http://www.python.org/dev/peps/pep-3136/ > >I think this is a good summary of various proposals that have been >floated in the past, plus some new ones. As a PEP, it falls short >because it doesn't pick a solution but merely offers a large menu of >possible options. Also, there is nothing about implementation yet.
I was hoping the community would pick their favorite option. And I planned to address implementation if the PEP was well received. >However, I'm rejecting it on the basis that code so complicated to >require this feature is very rare. In most cases there are existing >work-arounds that produce clean code, for example using 'return'. >While I'm sure there are some (rare) real cases where clarity of the >code would suffer from a refactoring that makes it possible to use >return, this is offset by two issues: > >1. The complexity added to the language, permanently. This affects not >only all Python implementations, but also every source analysis tool, >plus of course all documentation for the language. Not knowing anything about the implementation details, I can't argue with that. >2. My expectation that the feature will be abused more than it will be >used right, leading to a net decrease in code clarity (measured across >all Python code written henceforth). Lazy programmers are everywhere, >and before you know it you have an incredible mess on your hands of >unintelligible code. Are break / continue currently abused more than they are used right, or used to make code difficult to understand? I am trying to come up with an example of mis-use of labeled break or continue that is mitigated by the absence of labels, and I can't quite think of one. Maybe I'm being unimaginative. :) >I realize this is a heavy bar to pass, and somewhat subjective. That's >okay. There is real value in having a small language. Also, as I said, >while there are no past PEPs to document it, this has been brought up >and rejected many times before. So, I don't quite agree, but you're the boss. If this has been rejected before, I don't want to waste everybody's time discussing it again. Should I add your justification to the PEP and change it's status? -matt P.S. Thanks to everybody who read the PEP and commented. :) _______________________________________________ Python-3000 mailing list [email protected] http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
