On Wed, 11 Oct 2017 10:57 pm, Stefan Ram wrote:
> FWIW, in is book "Touch of Class" (2009) Bertrand Meyer writes:
>
> |Such instructions are just the old goto in sheep's clothing.
> |Treat them the same way as the original:
> |
> |/Touch of Methodology/:
> | Sticking to one-entry, one-exit build
Chris Angelico writes:
> while True:
> c = sys.stdin.read(1)
> if not c: break
> if c.isprintable(): text += c
> elif c == "\x08": text = text[:-1]
> # etc
> Can you write _that_ as a do-while?
I prefer to write that sort of thing with iterators:
for c in iter(lambda: sys.st
Op 16-04-17 om 19:07 schreef Terry Reedy:
> On 4/16/2017 11:35 AM, Michael Torrie wrote:
>> On 04/16/2017 07:57 AM, bartc wrote:
>>> But people just don't want it.
>>>
>>> /That/ is what surprises me, when people reject things that to me are
>>> no-brainers.
>
> Whereas to me, it is a no-brainer th
Ben Bacarisse wrote:
I fond the proportion on while True: loops surprising. Is there
something about Python that encourages that kind of loop?
Maybe because for-loops take care of most of the ordinary
cases in Python, leaving while-loops to cover the weird
ones, many of which need one or more
Christian Gollwitzer writes:
> Am 18.04.17 um 08:21 schrieb Chris Angelico:
>> On Tue, Apr 18, 2017 at 4:06 PM, Christian Gollwitzer
>> wrote:
>>> Am 18.04.17 um 02:18 schrieb Ben Bacarisse:
>>>
Thanks (and to Grant). IO seems to be the canonical example. Where
some languages would f
Am 18.04.17 um 08:21 schrieb Chris Angelico:
On Tue, Apr 18, 2017 at 4:06 PM, Christian Gollwitzer wrote:
Am 18.04.17 um 02:18 schrieb Ben Bacarisse:
Thanks (and to Grant). IO seems to be the canonical example. Where
some languages would force one to write
c = sys.stdin.read(1)
while c
Christian Gollwitzer :
> Am 18.04.17 um 02:18 schrieb Ben Bacarisse:
>> Python opts for
>>
>> while True:
>> c = sys.stdin.read(1)
>> if c != ' ': break
>
> This loop would be the archetypical do..while or repeat...until to me.
>
> do
> c = sys.stdin.read(1)
> while c== ' '
No,
On Tue, Apr 18, 2017 at 4:06 PM, Christian Gollwitzer wrote:
> Am 18.04.17 um 02:18 schrieb Ben Bacarisse:
>
>> Thanks (and to Grant). IO seems to be the canonical example. Where
>> some languages would force one to write
>>
>> c = sys.stdin.read(1)
>> while c == ' ':
>> c = sys.stdin.
Am 18.04.17 um 02:18 schrieb Ben Bacarisse:
Thanks (and to Grant). IO seems to be the canonical example. Where
some languages would force one to write
c = sys.stdin.read(1)
while c == ' ':
c = sys.stdin.read(1)
Python opts for
while True:
c = sys.stdin.read(1)
if c !=
On Tuesday, April 18, 2017 at 2:09:19 AM UTC+1, Paul Rubin wrote:
> Ben Bacarisse writes:
> > ? I get "AttributeError: 'itertools.dropwhile' object has no attribute
> > 'next'" from your example.
>
> Hmm, .next() worked ok for me in Python 2.7.5. Not sure what happened.
> Maybe something went wr
Ben Bacarisse :
> Python opts for
>
> while True:
> c = sys.stdin.read(1)
> if c != ' ': break
I opt for that in C and bash as well.
In fact, when I start writing a loop, I first type:
while True:
Once it is done, I might notice that the loop begins:
while True:
Gregory Ewing :
> Marko Rauhamaa wrote:
>> What I notice in my numbers is that about one half of my while loops
>> are "while True", and about a third of my loops are while loops.
>
> Out of curiosity, what proportion of your 'while True' loops are
> infinite? (I.e. no break, return or raise in th
On Tue, Apr 18, 2017 at 1:37 AM, MRAB wrote:
> In Python 3 it's:
>
> c = next(itertools.dropwhile(
> lambda c: c==' ',
> iter(lambda: sys.stdin.read(1),None)
> ))
iter's sentinel should be an empty string.
--
https://mail.python.org/mailman/listinfo/python-list
On 2017-04-18 02:09, Paul Rubin wrote:
Ben Bacarisse writes:
? I get "AttributeError: 'itertools.dropwhile' object has no attribute
'next'" from your example.
Hmm, .next() worked ok for me in Python 2.7.5. Not sure what happened.
Maybe something went wrong with my paste. Oh well.
Coming
Ben Bacarisse writes:
> ? I get "AttributeError: 'itertools.dropwhile' object has no attribute
> 'next'" from your example.
Hmm, .next() worked ok for me in Python 2.7.5. Not sure what happened.
Maybe something went wrong with my paste. Oh well.
> Coming from the lazy language Haskell, I find
Paul Rubin writes:
> Ben Bacarisse writes:
>> c = sys.stdin.read(1)
>> while c == ' ':
>> c = sys.stdin.read(1)
(for the record: I was not suggesting this was how you'd do it but how
you'd be forced to do it in some languages)
> c = itertools.dropwhile(
> lambda c: c==' ',
>
On 18/04/2017 01:23, Paul Rubin wrote:
Ben Bacarisse writes:
c = sys.stdin.read(1)
while c == ' ':
c = sys.stdin.read(1)
c = itertools.dropwhile(
lambda c: c==' ',
iter(lambda: sys.stdin.read(1),None)
).next()
I tried this but it doesn't like the .next.
I wanted t
Marko Rauhamaa writes:
> Ben Bacarisse :
>
>> Marko Rauhamaa writes:
>>> What I notice in my numbers is that about one half of my while loops
>>> are "while True", and about a third of my loops are while loops.
>>
>> I fo[u]nd the proportion on while True: loops surprising. Is there
>> something
Ben Bacarisse writes:
> c = sys.stdin.read(1)
> while c == ' ':
> c = sys.stdin.read(1)
c = itertools.dropwhile(
lambda c: c==' ',
iter(lambda: sys.stdin.read(1),None)
).next()
--
https://mail.python.org/mailman/listinfo/python-list
Marko Rauhamaa wrote:
What I notice in my numbers is that about one half of my while loops are
"while True", and about a third of my loops are while loops.
Out of curiosity, what proportion of your 'while True' loops
are infinite? (I.e. no break, return or raise in the loop.)
--
Greg
--
https:
On 2017-04-17, Ben Bacarisse wrote:
> Marko Rauhamaa writes:
>
>> Terry Reedy :
>>
>>> On 4/17/2017 3:11 AM, Marko Rauhamaa wrote:
Here's statistics from a medium-sized project of mine:
while True:34
while : 39
for ... in ...: 158
>>>
>>> As
On 17 April 2017 at 04:00, Steve D'Aprano wrote:
> On Mon, 17 Apr 2017 05:49 am, Dennis Lee Bieber wrote:
>
>> On Mon, 17 Apr 2017 02:48:08 +1000, Steve D'Aprano
>> declaimed the following:
>>
>>>On Sun, 16 Apr 2017 11:57 pm, bartc wrote:
>>>
But people just don't want it.
>>>
>>>Damn straig
Ben Bacarisse :
> Marko Rauhamaa writes:
>> What I notice in my numbers is that about one half of my while loops
>> are "while True", and about a third of my loops are while loops.
>
> I fo[u]nd the proportion on while True: loops surprising. Is there
> something about Python that encourages that
On 17/04/2017 19:02, Ben Bacarisse wrote:
Marko Rauhamaa writes:
Terry Reedy :
On 4/17/2017 3:11 AM, Marko Rauhamaa wrote:
Here's statistics from a medium-sized project of mine:
while True:34
while : 39
for ... in ...: 158
As I posted previously, the ratio
Marko Rauhamaa writes:
> Terry Reedy :
>
>> On 4/17/2017 3:11 AM, Marko Rauhamaa wrote:
>>> Here's statistics from a medium-sized project of mine:
>>>
>>>while True:34
>>>while : 39
>>>for ... in ...: 158
>>
>> As I posted previously, the ratio of for-loops in th
Terry Reedy :
> On 4/17/2017 3:11 AM, Marko Rauhamaa wrote:
>> Here's statistics from a medium-sized project of mine:
>>
>>while True:34
>>while : 39
>>for ... in ...: 158
>
> As I posted previously, the ratio of for-loops in the stdlib is about 7
> to 1.
What I
On 4/17/2017 3:11 AM, Marko Rauhamaa wrote:
Gregory Ewing :
bartc wrote:
Most of my loops start off as endless loops, until I can determine
the actual terminating condition, and where it best goes.
Interesting. My experience is quite different. Most of the loops I
write start off with me thi
Gregory Ewing :
> bartc wrote:
>> Most of my loops start off as endless loops, until I can determine
>> the actual terminating condition, and where it best goes.
>
> Interesting. My experience is quite different. Most of the loops I
> write start off with me thinking "Now I want to do this for eac
On Mon, 17 Apr 2017 05:49 am, Dennis Lee Bieber wrote:
> On Mon, 17 Apr 2017 02:48:08 +1000, Steve D'Aprano
> declaimed the following:
>
>>On Sun, 16 Apr 2017 11:57 pm, bartc wrote:
>>
>>> But people just don't want it.
>>
>>Damn straight. Now you get it. It's not about how easy it is to impleme
bartc wrote:
> - describing the various syntax forms;
> - explaining how they differ;
> - tutorials for beginners showing each form;
And you don't have to explain how an endless loop should be written as
'while True', meanwhile advising against using 'while 1'?
You don't have to mention i
On 16/04/2017 19:42, Chris Angelico wrote:
On Mon, Apr 17, 2017 at 4:21 AM, bartc wrote:
Here is a function from some old CPython source that appears to be something
to do with While statements:
static int
validate_while(node *tree)
{
...
Look, no comments! Are you going to castigate the dev
On Mon, Apr 17, 2017 at 4:21 AM, bartc wrote:
> Here is a function from some old CPython source that appears to be something
> to do with While statements:
>
> static int
> validate_while(node *tree)
> {
> int nch = NCH(tree);
> int res = (validate_ntype(tree, while_stmt)
>
On 16/04/2017 17:30, Steve D'Aprano wrote:
On Sun, 16 Apr 2017 10:06 pm, bartc wrote:
(The 30 Loc figure is with support for loops /in
general/ already in place, and is for /adding/ a new loop statement, in
this case 'while')
What part of *testing* and *documenting* do you not understand?
On Mon, 17 Apr 2017 03:00 am, Rustom Mody wrote:
> BTW I regard Steven's long list of things that youve missed such as
> regression tests, docs etc to be somewhat off the mark
> To see that try this experiment:
> Just add a feature to python that matters to you along with all these
> requirements
On 4/16/2017 11:35 AM, Michael Torrie wrote:
On 04/16/2017 07:57 AM, bartc wrote:
But people just don't want it.
/That/ is what surprises me, when people reject things that to me are
no-brainers.
Whereas to me, it is a no-brainer that we are better off *without*
multiple while/loop construct
On Sunday, April 16, 2017 at 7:27:49 PM UTC+5:30, bartc wrote:
> Technically, adding this one feature to Python /is/ trivial,
^
You are not paying attention bart and I am not likely to pursue this beyond this
post. I tried to say as are others that the substantive reasons to reject a
On Sun, 16 Apr 2017 11:57 pm, bartc wrote:
> Yet countless other, far more elaborate features /are/ added all the time.
Indeed. Because they are needed. Because they add functionality that Python
doesn't already have, or seriously improves the interface to that
functionality.
> Technically, add
On Sun, 16 Apr 2017 10:06 pm, bartc wrote:
> On 16/04/2017 03:51, Steve D'Aprano wrote:
>> On Sat, 15 Apr 2017 10:17 pm, bartc wrote:
>
>>> Yes, I'm constantly surprised at this, as such syntax has a very low
>>> cost (in my last compiler, supporting 'while' for example only added 30
>>> lines to
On 16/04/2017 15:22, Chris Angelico wrote:
On Sun, Apr 16, 2017 at 11:57 PM, bartc wrote:
Technically, adding this one feature to Python /is/ trivial, for example,
allowing while: as a synonym for while True:, but preferably using a new
keyword such as loop. Nothing else needs to be touched. An
On 04/16/2017 07:57 AM, bartc wrote:
> But people just don't want it.
>
> /That/ is what surprises me, when people reject things that to me are
> no-brainers.
I simply don't care about these missing loop constructs. Python works
great for what I use it for, and apparently works well for many pe
On Sun, Apr 16, 2017 at 11:57 PM, bartc wrote:
> Technically, adding this one feature to Python /is/ trivial, for example,
> allowing while: as a synonym for while True:, but preferably using a new
> keyword such as loop. Nothing else needs to be touched. And it could have
> been done right at the
On 16/04/2017 13:22, Rustom Mody wrote:
On Sunday, April 16, 2017 at 5:36:28 PM UTC+5:30, bartc wrote:
On 16/04/2017 03:51, Steve D'Aprano wrote:
On Sat, 15 Apr 2017 10:17 pm, bartc wrote:
Yes, I'm constantly surprised at this, as such syntax has a very low
cost (in my last compiler, support
On Sunday, April 16, 2017 at 5:36:28 PM UTC+5:30, bartc wrote:
> On 16/04/2017 03:51, Steve D'Aprano wrote:
> > On Sat, 15 Apr 2017 10:17 pm, bartc wrote:
>
> >> Yes, I'm constantly surprised at this, as such syntax has a very low
> >> cost (in my last compiler, supporting 'while' for example only
On 16/04/2017 03:51, Steve D'Aprano wrote:
On Sat, 15 Apr 2017 10:17 pm, bartc wrote:
Yes, I'm constantly surprised at this, as such syntax has a very low
cost (in my last compiler, supporting 'while' for example only added 30
lines to the project).
That's the advantage of writing your own p
Steve D'Aprano writes:
> I don't remember the language, but I remember seeing one generalisation of
> the repeat/do loop that puts the test in the middle, rather than at the
> start or end of the loop. If I remember it was something like:
>
> DO
> setup code # executed once only
> REPEAT
>
On Sat, 15 Apr 2017 10:17 pm, bartc wrote:
> On 15/04/2017 03:35, Rick Johnson wrote:
>> On Wednesday, April 12, 2017 at 8:44:30 AM UTC-5, bart...@gmail.com
>> wrote:
>
>> At a minimum, every language should offer
>> the following four loop-forms (using Python semantics):
>>
>> while CONDITIO
46 matches
Mail list logo
