[Python-ideas] Syntactic sugar to declare partial functions

Fri Aug 10 18:42:12 EDT 2018

On Fri, Aug 10, 2018 at 6:21 PM Abe Dillon <abedillon at gmail.com> wrote:

> [Neil Girdhar]
>
> I prefer partial since many programmers studied computer science
>
>
> Many did not. I studied electrical engineering and wouldn't have been able
> to tell you what the word 'partial' meant four years ago even though I've
> been programming in one form or another since the late nineties. Many
> programmers are scientists, engineers, financial analysts, etc. I'm pretty
> sure I know what a closure is or what currying is, but if you put me on the
> spot, I'd probably turn to Wikipedia to make sure I don't screw up the
> definition.
>
> [Neil Girdhar]
>
>> It makes the concepts easier to google.
>
>
> That can be an important criteria, but it can also be a red-herring. If an
> implementation is clear enough, few people would have to google it. If,
> however, you use obscure enough words like "lambda", people will google it
> every day and still find it confusing. The ternary expression is difficult
> to google if you don't know the jargon "ternary", but there's less of a
> need to google it because it's pretty obvious how it works based simply on
> its implementation.
>
> [Steven D'Aprano]
>
>> It's a clear, *generic* meaning that doesn't have any association with
>> partial application.
>> We'd be trying to create that association from scratch.
>
>
> Sure, that's a good point. I don't think that sounds like such a big
> problem, but I also don't hate 'partial'. I just prefer 'given'.
> At any rate, I don't find the google-ablilty argument super strong because
> there are many constructs that are difficult to google, but still pretty
> great (e.g. comprehensions).
>
Not that it matters, but comprehension is a standard term in mathematics
and computer science apparently:

https://en.wikipedia.org/wiki/List_comprehension
https://en.wikipedia.org/wiki/Set-builder_notation

> [Steven D'Aprano]
>
> > Words like 'partial', 'curry', 'lambda', and 'closure' are fine
>> > for text books, published papers, and technical discussion,
>> And programmers.
>>
>
> Yes, technical discussion among programmers.
>
> [Steven D'Aprano]
>
> Programming is a technical skill with its own jargon. Classes,
>> inheritence, exceptions, trampolining, processes, threads, protocols,
>> imports, decorator, builders... we are happy with all those, why should
>> we fear partial and lambda?
>
>
> I get that programming carries it's own jargon and I understand that it
> has a beneficial function. It can facilitate concise communication of
> nuanced concepts. It can also be a needlessly confusing way to convey
> otherwise simple concepts. In the latter case, it can feel like the intent
> is to create an air of superiority through esoteric language. I feel like
> "curry" and "lambda" are needlessly un-descriptive and confusing. "partial"
> really isn't that bad, I just prefer "given" because I think it's pretty
> clear. I've never heard of "trampolining", but if I had to guess: it's
> probably related to recursion that involves more than one function?
>
> I suspect that most programmers couldn't describe the difference between a
> type and a class.
> I suspect that most programmers couldn't tell you the difference between
> an exception or an error.
> I know that lots of programmers refer to the "__init__" method as a
> "constructor" instead of an "initializer".
>
> Precision is less of a problem In a programming language. `func.given`
> doesn't have dozens of possible meanings. It's meaning has to be completely
> unambiguous to the machine.
>
> [Steven D'Aprano]
>
> > but I think
>> > they would (or do in the case of 'lambda') harm Python.
>> That's an extreme overreaction.
>
>
> Extreme? I thought it was a rather benign opinion. I'm not exactly
> frothing at the mouth here. It's not like I'm declaring holy war on Python
> for using the word 'lambda'. I just think it was a mistake (and thatdeath
> should come to all non-believers).
>
> [Steven D'Aprano]
>
> Do you mean to imply that there are people who looked at Python, loved
>> the language, but decided to use something else because they didn't like
>> the choice of the keyword "lambda"?
>
>
> No. Not at all. Is that what you got out of my sentence? Am I really the
> one being extreme?
>

I didn't think you were being extreme at all.  I think you're making a
reasonable point about keeping things simple.

I disagree with you though when it comes to avoiding the technical terms.
It's easier for people new to a field to learn the jargon of that field
than it is to try to make it easier for them and by essentially creating a
whole lot more technical jargon.  (Even if that jargon uses common words.)

Your idea for "given" isn't obviously doing a partial function
application.  Someone might wonder if "given" is setting thread local
storage, or setting attributes on a callable class, or opening context
managers at call time…

>
> [Steven D'Aprano]
>
>> If not, in what way is Python harmed? Would it be faster if the keyword
>> was "function", or use less memory, or more expressive?
>
>
> I didn't realize I'd hit such a nerve. I think there are better ways that
> anonymous functions could have been implemented.  I've already said in past
> discussions, I think the expression should come before the signature
> because the signature is often obvious from context so placing it before
> the logic is kinda noisy. I don't know what the best syntax would have
> been, but I refuse to believe that an esoteric word from an esoteric branch
> of calculus with an arbitrary etymology was the absolute best choice
> available. I think the harm that choice caused is relatively minor, but I
> don't think it was a great choice. I'm truly sorry if I hurt your feelings.
>
> [Steven D'Aprano]
>
> Remember that to millions of programmers in the world, "function" is
>> just as much an obscure foreign piece of jargon they have to memorise as
>> "lambda" is to English-speakers.
>
>
> Maybe we should use Egyptian Hieroglyphs then. Even the playing field. It
> doesn't matter anyway, right? It's all nonsense to someone...
>
> Honestly, I don't think 'partial' is that bad. I just wanted to support
> your own comment:
>
>
> although possibly a less jargon name would be nicer:
>>     add1 = add.given(1)
>
>
> But you seem to have some grudge against me. I don't get all the outrage
> over what I thought was a fairly benign post.
> Did I do something to make you so angry at me? I'd like to resolve
> whatever it is instead of having to deal with this every time I post.
>
> On Fri, Aug 10, 2018 at 2:09 AM, Steven D'Aprano <steve at pearwood.info>
> wrote:
>
>> On Thu, Aug 09, 2018 at 01:32:00PM -0500, Abe Dillon wrote:
>> > I'd like to push for the less jargon-y `func.given()` version if this
>> gains
>> > traction. Not only is it shorter, it's a much more common term with a
>> clear
>> > meaning.
>>
>> It's a clear, *generic* meaning that doesn't have any association with
>> partial application.
>>
>> https://www.google.com/search?q=function+given
>>
>> We'd be trying to create that association from scratch.
>>
>>
>> > Words like 'partial', 'curry', 'lambda', and 'closure' are fine
>> > for text books, published papers, and technical discussion,
>>
>> And programmers.
>>
>> Programming is a technical skill with its own jargon. Classes,
>> inheritence, exceptions, trampolining, processes, threads, protocols,
>> imports, decorator, builders... we are happy with all those, why should
>> we fear partial and lambda?
>>
>>
>> > but I think
>> > they would (or do in the case of 'lambda') harm Python.
>>
>> That's an extreme overreaction.
>>
>> Do you mean to imply that there are people who looked at Python, loved
>> the language, but decided to use something else because they didn't like
>> the choice of the keyword "lambda"?
>>
>> If not, in what way is Python harmed? Would it be faster if the keyword
>> was "function", or use less memory, or more expressive?
>>
>> Remember that to millions of programmers in the world, "function" is
>> just as much an obscure foreign piece of jargon they have to memorise as
>> "lambda" is to English-speakers.
>>
>>
>> --
>> Steve
>> _______________________________________________
>> Python-ideas mailing list
>> Python-ideas at python.org
>> https://mail.python.org/mailman/listinfo/python-ideas
>> Code of Conduct: http://python.org/psf/codeofconduct/
>>
>
> --
>
> ---
> You received this message because you are subscribed to a topic in the
> Google Groups "python-ideas" group.
> To unsubscribe from this topic, visit
> https://groups.google.com/d/topic/python-ideas/jOMinivFCcQ/unsubscribe.
> To unsubscribe from this group and all its topics, send an email to
> python-ideas+unsubscribe at googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
> _______________________________________________
> Python-ideas mailing list
> Python-ideas at python.org
> https://mail.python.org/mailman/listinfo/python-ideas
> Code of Conduct: http://python.org/psf/codeofconduct/
>
> --
>
> ---
> You received this message because you are subscribed to a topic in the
> Google Groups "python-ideas" group.
> To unsubscribe from this topic, visit
> https://groups.google.com/d/topic/python-ideas/jOMinivFCcQ/unsubscribe.
> To unsubscribe from this group and all its topics, send an email to
> python-ideas+unsubscribe at googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-ideas/attachments/20180810/a49db954/attachment-0001.html>