Cameron Simpson added the comment: I'd like speak my support for bitwise ops on bytes and bytearray (agree, on equal lengths only).
I've got 2 arguments here: - readability: a ^ b, a | b and so forth are clear and direct - all the various incantation presented must be _understood_, not to mention invented anew by anyone wanting to do they same, with the same burden of getting it correct; of course one can say the same of any feature not already present in a language but that is trite; there are several ways to say this and all have varying degrees of speed, obtuseness and verbosity. And they're all SLOW. Regarding some of the counter arguments in the discussion: - gregory.p.smith in reply to cowlicks: "Security claims? Nonsense. This has nothing to do with security. It is *fundamentally impossible* to write constant time side channel attack resistant algorithms [...]" Maybe cowlicks should have said "reliable", though to my naive eye a normal implementation would be constant time for a given size. I would argue that the clarity and directness of just writing "a^b" immediately makes for trivially correct code, which itself is a necessary prerequisite for secure code. - gregory.p.smith again: "Neither of the above "look as nice" as a simple operator would. But they are at least both understandable and frankly about the same as what you would naively write in C for the task." This is not an argument against the feature. That one had to perform similar activitie in Python as in C merely reflects the present lack of these operators, not a preexisting gleaming sufficiency of operator richness. - Terry J. Reddy: "'XOR of two bytes in one place' strikes me as a thin excuse for a new feature that abbreviates a simple, short, one-liner". Christian Heimes's code has this single example, but anyone wanting to work on chunks of bytes may find themselves here. Just because a lot of things can be written/constructed as one liners doesn't mean they should be operators when (a) the operator is available (==unused) for this type, (b) the meaning of the operator is straight forward and intuitive and (c) any pure Python construction is both wordier and much slower. Anyway, I an for this feature, for the record. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue19251> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
