Re: [Python-ideas] A suggestion for a do...while loop

On 26 June 2017 at 10:25, Rob Cliffe wrote: > > > On 25/06/2017 12:58, Markus Meskanen wrote: >> >> I'm a huge fan of the do...while loop in other languages, and it would >> often be useful in Python too, when doing stuff like: >> >> while True: >> password =

Re: [Python-ideas] + operator on generators

On Sun, Jun 25, 2017 at 02:06:54PM +0200, lucas via Python-ideas wrote: > What about providing something like the following: > > a = (n for n in range(2)) > b = (n for n in range(2, 4)) > tuple(a + b) # -> 0 1 2 3 As Serhiy points out, this is going to conflict with existing use of

Re: [Python-ideas] + operator on generators

On Sunday, June 25, 2017, Danilo J. S. Bellini wrote: > On Sun, Jun 25, 2017 at 3:06 PM, lucas via Python-ideas < > python-ideas@python.org > > wrote: > >> I often use generators, and itertools.chain on them. >>

Re: [Python-ideas] Allow function to return multiple values

On 26 June 2017 at 01:14, rym...@gmail.com wrote: > IIRC I'm pretty sure the OP just didn't know about the existence of tuple > unpacking and the ability to use that to return multiple values. > Can be so, though it was not quite clear. The original OP's example function

Re: [Python-ideas] A suggestion for a do...while loop

On 25/06/2017 12:58, Markus Meskanen wrote: I'm a huge fan of the do...while loop in other languages, and it would often be useful in Python too, when doing stuff like: while True: password = input() if password == ...: break [...]I suggest [...] do: password =

Re: [Python-ideas] Improving Catching Exceptions

On 24/06/2017 11:03, Steven D'Aprano wrote: On Sat, Jun 24, 2017 at 01:02:55PM +1200, Greg Ewing wrote: In any case, this doesn't address the issue raised by the OP, which in this example is that if the implementation of bah.__getitem__ calls something else that raises an IndexError, there's

Re: [Python-ideas] Allow function to return multiple values

IIRC I'm pretty sure the OP just didn't know about the existence of tuple unpacking and the ability to use that to return multiple values. -- Ryan (ライアン) Yoko Shimomura, ryo (supercell/EGOIST), Hiroyuki Sawano >> everyone elsehttp://refi64.com On Jun 25, 2017 at 6:09 PM, > wrote: joannah

Re: [Python-ideas] Allow function to return multiple values

joannah nanjekye wrote: > [...] > >Today I was writing an example snippet for the book and needed to write a >function that returns two values something like this: > >def return_multiplevalues(num1, num2): > return num1, num2 > > I noticed that this actually returns a tuple of the values

Re: [Python-ideas] Reducing collisions in small dicts/sets

Two bits of new info: first, it's possible to get the performance of "double" without division, at least via this way: """ # Double hashing using Fibonacci multiplication for the increment. This # does about as well as `double`, but doesn't require division. # # The multiplicative constant

Re: [Python-ideas] + operator on generators

On Sun, Jun 25, 2017 at 3:06 PM, lucas via Python-ideas < python-ideas@python.org> wrote: > I often use generators, and itertools.chain on them. > What about providing something like the following: > > a = (n for n in range(2)) > b = (n for n in range(2, 4)) > tuple(a + b) # -> 0 1 2

Re: [Python-ideas] Runtime types vs static types

After rereading Koos' OP, I can now see that he was referring to a different kind of runtime type checking than I am interested in. There was a distinction I was unaware the core typing devs make between "typing-style types" and "classes" that I'll discuss further in the typing repo itself.

Re: [Python-ideas] Runtime types vs static types

On Sun, Jun 25, 2017 at 8:47 PM, Lucas Wiman wrote: > > ​Yes, but then `isinstance(tuple(range(100)), Tuple[int, ...])` > would be a difficult case. > > Yes, many methods on million-element tuples are slow. :-) > > Python usually chooses the more intuitive behavior

Re: [Python-ideas] Runtime types vs static types

> ​Yes, but then `isinstance(tuple(range(100)), Tuple[int, ...])` would be a difficult case. Yes, many methods on million-element tuples are slow. :-) Python usually chooses the more intuitive behavior over the faster behavior when there is a choice. IIUC, the objections don't have anything

Re: [Python-ideas] + operator on generators

On Sun, Jun 25, 2017 at 3:06 PM, lucas via Python-ideas < python-ideas@python.org> wrote: > I often use generators, and itertools.chain on them. > What about providing something like the following: > > a = (n for n in range(2)) > b = (n for n in range(2, 4)) > tuple(a + b) # -> 0 1 2

Re: [Python-ideas] Improving Catching Exceptions

On Sat, Jun 24, 2017 at 11:45:25PM +1000, Nick Coghlan wrote: > While I used to think that, I'm no longer sure it's true, as it seems > to me that a `contextlib.convert_exception` context manager could help > with both of them. Here is a recipe for such a context manager which is also useable

Re: [Python-ideas] Runtime types vs static types

On Sun, Jun 25, 2017 at 7:13 PM, Lucas Wiman wrote: [...] > >>> from typing import * > >>> isinstance(0, Union[int, float]) > Traceback (most recent call last): > File "", line 1, in > File "/Users/lucaswiman/.pyenv/versions/3.6/lib/python3.6/typing.py", > line 767,

Re: [Python-ideas] Runtime types vs static types

> > For some background on the removal of __instancecheck__, check the linked > issues here: > Thanks for the reference (the most relevant discussion starts here ). That said, I think I totally disagree with the underlying

Re: [Python-ideas] + operator on generators

I would like to add that for example numpy ndarrays are iterables, but they have an __add__ with completely different semantics, namely element-wise ( numerical) addition. So this proposal would conflict with existing libraries with iterable objects. Stephan Op 25 jun. 2017 2:51 p.m. schreef

Re: [Python-ideas] A suggestion for a do...while loop

On Jun 25, 2017 07:58, "Markus Meskanen" wrote: I'm a huge fan of the do...while loop in other languages, and it would often be useful in Python too, when doing stuff like: while True: password = input() if password == ...: break I've seen the pep 315

Re: [Python-ideas] Runtime types vs static types

For some background on the removal of __instancecheck__, check the linked issues here: https://github.com/python/typing/issues/135 -- Ryan (ライアン) Yoko Shimomura, ryo (supercell/EGOIST), Hiroyuki Sawano >> everyone elsehttp://refi64.com On Jun 25, 2017 at 8:11 AM, > wrote: On Sat, Jun 24,

Re: [Python-ideas] Runtime types vs static types

On Sat, Jun 24, 2017 at 11:30 PM, Lucas Wiman wrote: > ​ > On Sat, Jun 24, 2017 at 12:42 PM, Koos Zevenhoven > wrote: > >> There has been some discussion here and there concerning the differences >> between runtime types and static types (mypy etc.).

Re: [Python-ideas] + operator on generators

25.06.17 15:06, lucas via Python-ideas пише: I often use generators, and itertools.chain on them. What about providing something like the following: a = (n for n in range(2)) b = (n for n in range(2, 4)) tuple(a + b) # -> 0 1 2 3 This, from user point of view, is just as how

[Python-ideas] + operator on generators

Hello ! I often use generators, and itertools.chain on them. What about providing something like the following: a = (n for n in range(2)) b = (n for n in range(2, 4)) tuple(a + b) # -> 0 1 2 3 This, from user point of view, is just as how the __add__ operator works on lists and

Re: [Python-ideas] A suggestion for a do...while loop

25.06.17 14:58, Markus Meskanen пише: I'm a huge fan of the do...while loop in other languages, and it would often be useful in Python too, when doing stuff like: while True: password = input() if password == ...: break In this particular case you could write: for

[Python-ideas] A suggestion for a do...while loop

I'm a huge fan of the do...while loop in other languages, and it would often be useful in Python too, when doing stuff like: while True: password = input() if password == ...: break I've seen the pep 315 which got rejected, and I believe these two suggestions were mostly focused