[Python-Dev] Adding bytes.frombuffer() constructor to PEP 467 (was: [Python-ideas] Adding bytes.frombuffer() constructor (original) (raw)

Chris Barker - NOAA Federal chris.barker at noaa.gov
Tue Oct 18 11:28:43 EDT 2016

Method proliferation on builtins is a Big Deal(TM) I wanted to quantify this concept, so here's a quick metric that helps convey how every time we add a new builtin method we're immediately making Python harder to comprehend: def getbuiltintypes(): ... import builtins ... return {name:obj for name, obj in vars(builtins).items() if isinstance(obj, type) and not (name.startswith("") or_ issubclass(obj, BaseException))} ... len(getbuiltintypes()) 26

Sure -- adding a new builtin is s big deal.

def getbuiltinmethods(): ... return [(name, methodname) for name, obj in getbuiltintypes().items() for methodname, method in vars(obj).items() if not methodname.startswith("")]_ ... len(getbuiltinmethods()) 230

So what? No one looks in all the methods of builtins at once. If we have anything like an OO System (and python builtins only sort of do...) then folks look for a built in that they need, and only then look at its methods.

If you need to work with bytes, you'll look at the bytes object and bytarray object. Having to go find some helper function module to know to efficiently do something with bytes is VERY non-discoverable!

bytes and bytarray are already low-level objects -- adding low-level functionality to them makes perfect sense.

And no, this is not just for asycio at all -- it's potentially useful for any byte manipulation.

+1 on a frombuffer() method.

Putting special purpose functionality behind an import gate helps to provide a more explicit context of use

This is a fine argument for putting bytearray in a separate module -- but that ship has sailed. The method to construct a bytearray from a buffer belongs with the bytearray object.

-CHB

More information about the Python-Dev mailing list