[Python-ideas] Give regex operations more sugar

Brendan Barnwell brenbarn at brenbarn.net
Thu Jun 14 03:12:34 EDT 2018

On 2018-06-13 23:37, Chris Angelico wrote:
>>         str.re can be a descriptor object which "knows" which string
>> instance it is bound to.  This kind of thing is common in many libraries.
>> Pandas for example has all kinds of things like df.loc[1:3],
>> df.column.str.startswith('blah'), etc.  The "loc" and "str" attributes give
>> objects which are bound (in the sense that bound methods are bound) to the
>> objects on which they are accessed, so when you use these attributes to do
>> things, the effect takes account of on the "root" object on which you
>> accessed the attribute.
>>         Personally I think this is a great way to reduce namespace clutter
>> and group related functionality without having to worry about using up all
>> the short or "good" names at the top level.  I'm not sure I agree with the
>> specific proposal here for allowing regex operations on strings, but if we
>> do do it, this would be a good way to do it.
> How is this materially different from:
> "some string".re_match(...)
> ? It's not a grouped namespace in any technical sense, but to any
> human, a set of methods that start with a clear prefix is functionally
> a group.

	Do you really mean that? :-)

	As far as I can see, by the same argument, there is no need for 
modules.  Instead of math.sin and math.cos, we can just have math_sin 
and math_cos.  Instead of os.path.join we can just have os_path_join. 
And so on.  Just one big namespace for everything.  But as we all know, 
namespaces are one honking great idea!

	Now, of course there are other advantages to modules (such as being 
able to save the time of loading things you don't need), and likewise 
there are other advantages to this descriptor mechanism in some cases. 
(For instance, sometimes the sub-object may want to hold state if it is 
going to be passed around and used later, rather than just having a 
method called and being thrown away immediately.)  But I think it's 
clear that in both cases the namespacing is also nice.

Brendan Barnwell
"Do not follow where the path may lead.  Go, instead, where there is no 
path, and leave a trail."
    --author unknown

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