On 26.03.2016 18:04, Terry Reedy wrote:

So proposed all(iterable, predicate) == all(map(predicate, iterable))

I am no native English speaker. Is predicate the right word for this? Two observations: 1) I recently saw a similar request to another "aggregate" function. 2) I can comprehend why all(map(predicate, iterable)) is harder to write. However, somehow I feel all(iterable, predicate) is harder to maintain. Because of 2) I am -1 on this. :) One could further argue that we need a another "predicate" for filtering: all(iterable, map, filter) etc. I get the feeling we would rebuilding things over and over again: list comprehensions, filter, map, itertools, for-loops etc. What about "sum", "max" etc? They all could need map + filter. Additional thought: I think the underlying issue is the number of parentheses involved. I myself somehow avoid nesting too many function calls into one line just because of that; not because of the complexity involved but because it looks strange. Of course the number of parentheses involved is an indicator of the complexity. Not sure if there is another way of handling this; maybe piping or something. Would be great if we could avoid writing ))) or ))))). Best, Sven

On Mar 29, 2016 12:49 PM, "Michael Selik" wrote:

On Tue, Mar 29, 2016 at 9:15 AM Sven R. Kunze wrote:

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On 26.03.2016 18:04, Terry Reedy wrote:

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So proposed all(iterable, predicate) == all(map(predicate, iterable))

I am no native English speaker. Is predicate the right word for this?

I'm not sure being a native speaker would help in this case. :-)

One reasonably common definition of "predicate": a function that tests a

condition on a value and returns True/False. Some folks define it more broadly, but then the word loses its usefulness as distinct from other kinds of functions. The usage of "predicate" here comes from predicate logic, or more specifically the usage of the term in languages like Lisp. Where Python says ``'42'.isnumeric()`` a lisper might say ``(numberp 42)``, the "p" suffix indicating that it's a predicate function.

https://www.cs.cmu.edu/Groups/AI/html/cltl/clm/node69.html

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I get the feeling we would rebuilding things over and over again: list comprehensions, filter, map, itertools, for-loops etc.

Certainly feels like it.

* "predicate" seems to be the common term * (predicate, iterable) seems to be the, at least in Python, common function signature * itertools.ifilter (predicate, iterable) https://docs.python.org/2/library/itertools.html#itertools.ifilter * python3: filter(function, iterable)) https://docs.python.org/3/library/functions.html#filter * toolz: *(predicate, iterable) * funcy.ifilter(pred, seq) http://funcy.readthedocs.org/en/stable/seqs.html#transform-and-filter ... "iterable" / sequence

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I think the underlying issue is the number of parentheses involved. I myself somehow avoid nesting too many function calls into one line just because of that; not because of the complexity involved but because it looks strange.

Same here. But I don't mind the occasional throwaway variable. When it's

a multi-step process, a good name for an intermediate stage helps me think. much easier to debug with e.g. ipdb, pdb, when there are intermediate variables. IDK if there are any less references to track without intermediate variables?

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Of course the number of parentheses involved is an indicator of the complexity. Not sure if there is another way of handling this;

* git commit * :PymodeLintAuto #vim * git diff * git commit ... or gg=G #vim

maybe piping or something. Would be great if we could

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avoid writing ))) or ))))).

http://xkcd.com/297/

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On 29.03.2016 19:48, Michael Selik wrote:

On Tue, Mar 29, 2016 at 9:15 AM Sven R. Kunze mailto:srkunze@mail.de> wrote:

On 26.03.2016 18:04, Terry Reedy wrote: > So proposed all(iterable, predicate) == all(map(predicate, iterable))

I am no native English speaker. Is predicate the right word for this?

I'm not sure being a native speaker would help in this case. :-)

One reasonably common definition of "predicate": a function that tests a condition on a value and returns True/False. Some folks define it more broadly, but then the word loses its usefulness as distinct from other kinds of functions. The usage of "predicate" here comes from predicate logic, or more specifically the usage of the term in languages like Lisp. Where Python says ``'42'.isnumeric()`` a lisper might say ``(numberp 42)``, the "p" suffix indicating that it's a predicate function.

https://www.cs.cmu.edu/Groups/AI/html/cltl/clm/node69.html

I see. That was why I would associate "predicate" more with filter than with map.

I get the feeling we would rebuilding things over and over again: list comprehensions, filter, map, itertools, for-loops etc.

Certainly feels like it.

:)

I think the underlying issue is the number of parentheses involved. I myself somehow avoid nesting too many function calls into one line just because of that; not because of the complexity involved but because it looks strange.

Same here. But I don't mind the occasional throwaway variable. When it's a multi-step process, a good name for an intermediate stage helps me think.

Yep. That is how it should be done then.

Of course the number of parentheses involved is an indicator of the complexity. Not sure if there is another way of handling this; maybe piping or something. Would be great if we could avoid writing ))) or ))))).

http://xkcd.com/297/

:D