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Feature suggestion -- return if true

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  Feature suggestion -- return if true zildjohn01 <zildjohn01@gmail.com> - 2011-04-11 16:17 -0700
    Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 10:27 +1000
      Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 01:44 +0000
        Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:12 +1000
          Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 02:18 +0000
            Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:44 +1000
              Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 13:42 +0000
              Re: Feature suggestion -- return if true "Martin v. Loewis" <martin@v.loewis.de> - 2011-04-17 12:03 +0200
                Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-18 09:36 +1000
        Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:20 +1000
        Re: Feature suggestion -- return if true Zero Piraeus <schesis@gmail.com> - 2011-04-11 22:43 -0400
        Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 12:44 +1000
        Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 12:49 +1000
        Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 12:59 +1000
        Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 13:01 +1000
          Re: Feature suggestion -- return if true Nobody <nobody@nowhere.com> - 2011-04-12 07:08 +0100
            Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-12 16:21 +1000
              Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-12 10:52 +0000
              Re: Feature suggestion -- return if true scattered <tooscattered@gmail.com> - 2011-04-12 03:55 -0700
                Re: Feature suggestion -- return if true "Colin J. Williams" <cjw@ncf.ca> - 2011-04-12 10:01 -0400
              Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 13:50 +0000
          Re: Feature suggestion -- return if true Grant Edwards <invalid@invalid.invalid> - 2011-04-12 13:44 +0000
        Re: Feature suggestion -- return if true Westley Martínez <anikom15@gmail.com> - 2011-04-12 07:05 -0700
          Re: Feature suggestion -- return if true scattered <tooscattered@gmail.com> - 2011-04-12 07:58 -0700
            Re: Feature suggestion -- return if true Westley Martínez <anikom15@gmail.com> - 2011-04-12 15:45 -0700
            Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-13 08:52 +1000
          Re: Feature suggestion -- return if true zildjohn01 <zildjohn01@gmail.com> - 2011-04-12 11:25 -0700
            Re: Feature suggestion -- return if true Terry Reedy <tjreedy@udel.edu> - 2011-04-12 15:14 -0400
            Re: Feature suggestion -- return if true alex23 <wuwei23@gmail.com> - 2011-04-12 21:05 -0700
      Re: Feature suggestion -- return if true Teemu Likonen <tlikonen@iki.fi> - 2011-04-12 21:00 +0300
        Re: Feature suggestion -- return if true Ian Kelly <ian.g.kelly@gmail.com> - 2011-04-12 12:25 -0600
          Re: Feature suggestion -- return if true Neil Cerutti <neilc@norwich.edu> - 2011-04-12 20:13 +0000
            Re: Feature suggestion -- return if true Neil Cerutti <neilc@norwich.edu> - 2011-04-12 20:16 +0000
        Re: Feature suggestion -- return if true Ian Kelly <ian.g.kelly@gmail.com> - 2011-04-12 12:29 -0600
        Re: Feature suggestion -- return if true Paul Rudin <paul.nospam@rudin.co.uk> - 2011-04-12 19:28 +0100
        Re: Feature suggestion -- return if true Chris Rebert <clp2@rebertia.com> - 2011-04-12 13:26 -0700
        Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-13 08:34 +1000
        Re: Feature suggestion -- return if true Ethan Furman <ethan@stoneleaf.us> - 2011-04-12 16:06 -0700
          Re: Feature suggestion -- return if true Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2011-04-21 12:13 +0200
        Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-13 09:12 +1000
        Re: Feature suggestion -- return if true Westley Martínez <anikom15@gmail.com> - 2011-04-12 16:15 -0700
        Re: Feature suggestion -- return if true Ethan Furman <ethan@stoneleaf.us> - 2011-04-12 16:48 -0700
          Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-13 00:03 +0000
            Re: Feature suggestion -- return if true Ethan Furman <ethan@stoneleaf.us> - 2011-04-12 19:42 -0700
            Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-13 13:00 +1000
            Re: Feature suggestion -- return if true James Mills <prologic@shortcircuit.net.au> - 2011-04-13 13:28 +1000
        Re: Feature suggestion -- return if true Teemu Likonen <tlikonen@iki.fi> - 2011-04-13 13:58 +0300
    Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 10:46 +1000
      Re: Feature suggestion -- return if true Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-17 16:21 +1200
        Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-17 14:31 +1000
        Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-17 08:45 +0000
          Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-17 19:07 +1000
            Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-17 15:23 +0000
          Re: Feature suggestion -- return if true Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-18 12:25 +1200
          Re: Feature suggestion -- return if true Dave Angel <davea@ieee.org> - 2011-04-17 22:04 -0400
          Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-18 12:10 +1000
            Re: Feature suggestion -- return if true Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-19 12:35 +1200
              Re: Feature suggestion -- return if true Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2011-04-19 09:42 +0300
                Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-19 17:01 +1000
        Re: Feature suggestion -- return if true "D'Arcy J.M. Cain" <darcy@druid.net> - 2011-04-17 08:33 -0400
          Re: Feature suggestion -- return if true Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-04-17 15:10 +0000
          Re: Feature suggestion -- return if true aahz@pythoncraft.com (Aahz) - 2011-04-18 09:11 -0700
        Re: Feature suggestion -- return if true Greg Ewing <greg.ewing@canterbury.ac.nz> - 2011-04-18 11:09 +1200
    Re: Feature suggestion -- return if true Chris Angelico <rosuav@gmail.com> - 2011-04-12 10:51 +1000
    Re: Feature suggestion -- return if true Paul Rubin <no.email@nospam.invalid> - 2011-04-11 23:58 -0700
      Re: Feature suggestion -- return if true John Roth <johnroth1@gmail.com> - 2011-04-12 06:16 -0700
      Re: Feature suggestion -- return if true Mel <mwilson@the-wire.com> - 2011-04-12 11:12 -0400

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#3047

On 2011-04-12, James Mills <prologic@shortcircuit.net.au> wrote:
> On Tue, Apr 12, 2011 at 4:08 PM, Nobody <nobody@nowhere.com> wrote:
>> It should be abundantly clear that this only returns if the expression is
>> considered true, otherwise it continues on to the following statements.
>
> Uggh come on guys. We've been over this.
> You cannot make that assumption.

You most certain can.  Try it yourself in an interpreter.  The
OP's code snippit will not return if expr is false, rather it will
continue executing in the current context:

>>> def foo(expr):
...   __temp__ = expr                         # these two lines are
...   if __temp__:  return __temp__           # the OP's code snippet
...   print "the code snippet did not return"
... 
>>> print foo(9)
9
>>> 
>>> print foo(0)
the code snippet did not return
None
>>> 

-- 
Grant Edwards               grant.b.edwards        Yow! One FISHWICH coming
                                  at               up!!
                              gmail.com            

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#3046

On 2011-04-12, James Mills <prologic@shortcircuit.net.au> wrote:
> On Tue, Apr 12, 2011 at 12:44 PM, Chris Angelico <rosuav@gmail.com> wrote:
>> That's still not equivalent. "return expr or None" will always
>> terminate the function. The OP's request was for something which would
>> terminate the function if and only if expr is non-false.
>
> The OP did not state this at all.
> There was never any mention of early termination
> of the function iif expr was True.

The OP said he wanted something with the semantics of

   _temp_ = expr
   if _temp_: return _temp_

That code snippet does not return if expr is false.  What you proposed
returns None when expr is false.

-- 
Grant Edwards               grant.b.edwards        Yow! Well, I'm INVISIBLE
                                  at               AGAIN ... I might as well
                              gmail.com            pay a visit to the LADIES
                                                   ROOM ...

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#3051

On Tue, 2011-04-12 at 12:44 +1000, Chris Angelico wrote:
> On Tue, Apr 12, 2011 at 12:20 PM, James Mills
> <prologic@shortcircuit.net.au> wrote:
> > On Tue, Apr 12, 2011 at 12:18 PM, Jason Swails <jason.swails@gmail.com> wrote:
> >> This is only true if n < 5.  Otherwise, the first returns None and the
> >> second returns False.
> >
> > Which is why I said:
> >
> > return expr or None
> >
> > But hey let's argue the point to death!
> 
> That's still not equivalent. "return expr or None" will always
> terminate the function. The OP's request was for something which would
> terminate the function if and only if expr is non-false.
> 
> Chris Angelico

def bs(x):
    while not x:
        <modify x>
    return x

Am I wrong here?

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#3053

On Apr 12, 10:05 am, Westley Martínez <aniko...@gmail.com> wrote:
> On Tue, 2011-04-12 at 12:44 +1000, Chris Angelico wrote:
> > On Tue, Apr 12, 2011 at 12:20 PM, James Mills
> > <prolo...@shortcircuit.net.au> wrote:
> > > On Tue, Apr 12, 2011 at 12:18 PM, Jason Swails <jason.swa...@gmail.com> wrote:
> > >> This is only true if n < 5.  Otherwise, the first returns None and the
> > >> second returns False.
>
> > > Which is why I said:
>
> > > return expr or None
>
> > > But hey let's argue the point to death!
>
> > That's still not equivalent. "return expr or None" will always
> > terminate the function. The OP's request was for something which would
> > terminate the function if and only if expr is non-false.
>
> > Chris Angelico
>
> def bs(x):
>     while not x:
>         <modify x>
>     return x
>
> Am I wrong here?- Hide quoted text -
>
> - Show quoted text -

I don't think that this is equivalent. The OP's original idea doesn't
involve a loop, but this does - how could that be equivalent?

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#3093

On Tue, 2011-04-12 at 07:58 -0700, scattered wrote:
> On Apr 12, 10:05 am, Westley Martínez <aniko...@gmail.com> wrote:
> > On Tue, 2011-04-12 at 12:44 +1000, Chris Angelico wrote:
> > > On Tue, Apr 12, 2011 at 12:20 PM, James Mills
> > > <prolo...@shortcircuit.net.au> wrote:
> > > > On Tue, Apr 12, 2011 at 12:18 PM, Jason Swails <jason.swa...@gmail.com> wrote:
> > > >> This is only true if n < 5.  Otherwise, the first returns None and the
> > > >> second returns False.
> >
> > > > Which is why I said:
> >
> > > > return expr or None
> >
> > > > But hey let's argue the point to death!
> >
> > > That's still not equivalent. "return expr or None" will always
> > > terminate the function. The OP's request was for something which would
> > > terminate the function if and only if expr is non-false.
> >
> > > Chris Angelico
> >
> > def bs(x):
> >     while not x:
> >         <modify x>
> >     return x
> >
> > Am I wrong here?- Hide quoted text -
> >
> > - Show quoted text -
> 
> I don't think that this is equivalent. The OP's original idea doesn't
> involve a loop, but this does - how could that be equivalent?

Not OP's idea, Angelico's.

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#3096

On Wed, Apr 13, 2011 at 8:45 AM, Westley Martínez <anikom15@gmail.com> wrote:
>> I don't think that this is equivalent. The OP's original idea doesn't
>> involve a loop, but this does - how could that be equivalent?
>
> Not OP's idea, Angelico's.

I didn't actually advocate a loop, but that method could work too. It
all depends on the actual code being executed. I'd still be in favour
of shor-circuit Or operators for this, although it does cost
readability.

Side point: Interesting that I'm referred to by surname here. Seems
there's a large number of people here named Chris - fits my theory
that geeks are often named Chris, and vice versa!

Chris Angelico
aka Rosuav

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#3072

Wow. Two dozen replies, the majority of which are arguing over whether
the end of my snippet is reachable. I thought the behavior of if
statements was well-established by this point.

Regardless of James Mills's coding prowess, I suppose I should follow
his advice and repost this to the python-ideas list instead.

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#3079

On 4/12/2011 2:25 PM, zildjohn01 wrote:
> Wow. Two dozen replies, the majority of which are arguing over whether
> the end of my snippet is reachable. I thought the behavior of if
> statements was well-established by this point.
>
> Regardless of James Mills's coding prowess, I suppose I should follow
> his advice and repost this to the python-ideas list instead.

I would not. I am 99.99% sure both the syntax (introducing '?') and the 
idea will be rejected.

-- 
Terry Jan Reedy

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#3114

zildjohn01 <zildjoh...@gmail.com> wrote:
> Regardless of James Mills's coding prowess[...]

James is the sole dev of a very handy & elegant event framework:
https://bitbucket.org/prologic/circuits/ Can you point out any
equivalent achievements so we can compare?

And make sure to carry that attitude of smug superiority over to
python-ideas, they love it there.

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#3068

* 2011-04-12T10:27:55+10:00 * James Mills wrote:

> On Tue, Apr 12, 2011 at 9:17 AM, zildjohn01 <zildjohn01@gmail.com> wrote:
>> This is an idea I've had bouncing around in my head for a long time
>> now. I propose the following syntax:
>
> Maybe this is more appropriare for the python-ideas list ?
>
>>    return? expr
>
> This syntax does not fit well within python ideology.

I'm a simple Lisp guy who wonders if it is be possible to add some kind
of macros to the language. Then features like this could be added by
anybody. Lisp people do this all the time and there is no need for
feature requests or any discussions.

    (with-returns
       ;; some code
       (return-if foo)
       ;; more code
       (return-if bar))

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#3073

On Tue, Apr 12, 2011 at 12:00 PM, Teemu Likonen <tlikonen@iki.fi> wrote:
> I'm a simple Lisp guy who wonders if it is be possible to add some kind
> of macros to the language. Then features like this could be added by
> anybody. Lisp people do this all the time and there is no need for
> feature requests or any discussions.
>
>    (with-returns
>       ;; some code
>       (return-if foo)
>       ;; more code
>       (return-if bar))

Flow-control macros were suggested as part of PEP 343, but they were
rejected by Guido based on this rant:

http://blogs.msdn.com/b/oldnewthing/archive/2005/01/06/347666.aspx

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#3084

On 2011-04-12, Ian Kelly <ian.g.kelly@gmail.com> wrote:
> Flow-control macros were suggested as part of PEP 343, but they
> were rejected by Guido based on this rant:
>
> http://blogs.msdn.com/b/oldnewthing/archive/2005/01/06/347666.aspx

Flow control macros don't seem to create problems that exceptions
didn't already create. Were context managers in existence at the
time?

-- 
Neil Cerutti

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#3085

On 2011-04-12, Neil Cerutti <neilc@norwich.edu> wrote:
> On 2011-04-12, Ian Kelly <ian.g.kelly@gmail.com> wrote:
>> Flow-control macros were suggested as part of PEP 343, but
>> they were rejected by Guido based on this rant:
>>
>> http://blogs.msdn.com/b/oldnewthing/archive/2005/01/06/347666.aspx
>
> Flow control macros don't seem to create problems that
> exceptions didn't already create. Were context managers in
> existence at the time?

Oops! Exceedingly ignorant question considering the actual
content of PEP 343.

-- 
Neil Cerutti

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#3074

On Tue, Apr 12, 2011 at 12:25 PM, Ian Kelly <ian.g.kelly@gmail.com> wrote:
> On Tue, Apr 12, 2011 at 12:00 PM, Teemu Likonen <tlikonen@iki.fi> wrote:
>> I'm a simple Lisp guy who wonders if it is be possible to add some kind
>> of macros to the language. Then features like this could be added by
>> anybody. Lisp people do this all the time and there is no need for
>> feature requests or any discussions.
>>
>>    (with-returns
>>       ;; some code
>>       (return-if foo)
>>       ;; more code
>>       (return-if bar))
>
> Flow-control macros were suggested as part of PEP 343, but they were
> rejected by Guido based on this rant:
>
> http://blogs.msdn.com/b/oldnewthing/archive/2005/01/06/347666.aspx

Sorry, that should have been PEP 340, which was rejected in favor of 343.

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#3078

Teemu Likonen <tlikonen@iki.fi> writes:

> I'm a simple Lisp guy who wonders if it is be possible to add some kind
> of macros to the language...

As a (now somewhat lapsed) long-time lisp programmer I sympathise with
the sentiment, but suspect that it's not going to gain serious traction
in python circles.

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#3087

On Tue, Apr 12, 2011 at 11:00 AM, Teemu Likonen <tlikonen@iki.fi> wrote:
> * 2011-04-12T10:27:55+10:00 * James Mills wrote:
>> On Tue, Apr 12, 2011 at 9:17 AM, zildjohn01 <zildjohn01@gmail.com> wrote:
>>> This is an idea I've had bouncing around in my head for a long time
>>> now. I propose the following syntax:
>>
>> Maybe this is more appropriare for the python-ideas list ?
>>
>>>    return? expr
>>
>> This syntax does not fit well within python ideology.
>
> I'm a simple Lisp guy who wonders if it is be possible to add some kind
> of macros to the language. Then features like this could be added by
> anybody. Lisp people do this all the time and there is no need for
> feature requests or any discussions.

I think Ben "Yahtzee" Croshaw's comments on open-world sandbox video
games (of all things) have a lot of applicability to why allowing
full-on macros can be a bad idea.

Paraphrasing liberally from his review of Far Cry 2:
"Letting the [programmer] create their own [language constructs is]
always done at the expense of proper [orthogonality, elegance, and
coherence]. Maybe sometimes I don't want to create my own [programming
language] experience. Maybe I want to have an experience that's been
carefully crafted by professional [language] designers and
[architects]. But [a] delusion has arisen that absolutely anyone can
contribute something valid, regardless of qualifications. In TV news
for example, you'll often see them pause to hear the opinion of a
seventy-five-year-old housebound racist from Lemington. And now you
get [languages] like [Lisp] that rely heavily on user-made [language
constructs]. Which I prophesise doom for, because most people are not
[language] designers, and you're just going to end up with oceans of
slurry, as indeed we have. It's like giving someone a stack of paper
and a [pen] and claiming that that's as good as the latest [New York
Times] bestseller."

IOW, a language is usually better for having such discussions and
having a fairly coherent worldview enforced by the existence of a
managing authority.

Cheers,
Chris
--
http://blog.rebertia.com

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#3092

On Wed, Apr 13, 2011 at 6:26 AM, Chris Rebert <clp2@rebertia.com> wrote:
> Paraphrasing liberally from his review of Far Cry 2:
> "Letting the [programmer] create their own [language constructs is]
> always done at the expense of proper [orthogonality, elegance, and
> coherence]. Maybe sometimes I don't want to create my own [programming
> language] experience. Maybe I want to have an experience that's been
> carefully crafted by professional [language] designers and
> [architects]. But [a] delusion has arisen that absolutely anyone can
> contribute something valid, regardless of qualifications. In TV news
> for example, you'll often see them pause to hear the opinion of a
> seventy-five-year-old housebound racist from Lemington. And now you
> get [languages] like [Lisp] that rely heavily on user-made [language
> constructs]. Which I prophesise doom for, because most people are not
> [language] designers, and you're just going to end up with oceans of
> slurry, as indeed we have. It's like giving someone a stack of paper
> and a [pen] and claiming that that's as good as the latest [New York
> Times] bestseller."
>
> IOW, a language is usually better for having such discussions and
> having a fairly coherent worldview enforced by the existence of a
> managing authority.

Are we done with this discussion yet ? :)
*sigh* It was a slow day yesterday and I have
a funny feeling it's going to be the same today!

Regardless of anyone's subjective opinions as to what
was clear - I still stand by what I said.

Nice comments btw Chris :)

cheers
James

-- 
-- James Mills
--
-- "Problems are solved by method"

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#3097

James Mills wrote:
> Are we done with this discussion yet ? :)
> *sigh* It was a slow day yesterday and I have
> a funny feeling it's going to be the same today!
> 
> Regardless of anyone's subjective opinions as to what
> was clear - I still stand by what I said.

I think I see your point -- the OP said:
-->    _temp = expr
-->    if _temp: return _temp

which is where you're getting
-->    return _temp or None

However, most everyone ('cept you, it seems! ;) understood that there 
would be more lines of code such that if bool(expr) == False no return 
is executed and the function keeps going merrily along.  Like this:
--> def func():
-->     var1 = something()
-->     var2 = something_else('this')
-->     return? var1.hobgle(var2)
-->     var3 = last_resort(var1)
-->     return var3.wiglat(var2)


Looking back at the whole post now, I see nothing there to concretely 
make that point except the question mark on the return.

Hope this helps.

~Ethan~

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#3784

Am 13.04.2011 01:06, schrieb Ethan Furman:

> --> def func():
> --> var1 = something()
> --> var2 = something_else('this')
> --> return? var1.hobgle(var2)
> --> var3 = last_resort(var1)
> --> return var3.wiglat(var2)

This makes me think of a decorator which can mimic the wantend behaviour:

def getfirst(f):
     from functools import wraps
     @wraps(f)
     def func(*a, **k):
         for i in f(*a, **k):
             if i: return i
     return func

# [BTW: a kind of "return decorator" would be nice here ;-)]

@getfirst
def func():
     var1 = something()
     var2 = something_else('this')
     yield var1.hobgle(var2)
     var3 = last_resort(var1)
     yield var3.wiglat(var2)
     yield "Even that did not work."

This has the advantage of being flexible about which condition to 
evaluate: maybe the func does return tuples of which only the 2nd part 
is relevant concerning the check. Then just do


def getfirst(f):
     from functools import wraps
     @wraps(f)
     def func(*a, **k):
         for i in f(*a, **k):
             if i[1]: return i
     return func

@getfirst
def func():
     var1 = something()
     var2 = something_else('this')
     yield "first try", var1.hobgle(var2)
     var3 = last_resort(var1)
     yield "second try", var3.wiglat(var2)
     yield "default value", "Even that did not work."


Disclaimer: Untested, but you should get the idea.

Thomas

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#3099

On Wed, Apr 13, 2011 at 9:06 AM, Ethan Furman <ethan@stoneleaf.us> wrote:
> I think I see your point -- the OP said:
> -->    _temp = expr
> -->    if _temp: return _temp
>
> which is where you're getting
> -->    return _temp or None
>
> However, most everyone ('cept you, it seems! ;) understood that there would
> be more lines of code such that if bool(expr) == False no return is executed
> and the function keeps going merrily along.  Like this:
> --> def func():
> -->     var1 = something()
> -->     var2 = something_else('this')
> -->     return? var1.hobgle(var2)
> -->     var3 = last_resort(var1)
> -->     return var3.wiglat(var2)
>
>
> Looking back at the whole post now, I see nothing there to concretely make
> that point except the question mark on the return.

Ethan I actually really appreciate your comments. Thank you!

Yes I do understand there is probably more code that
follows the return? - but I made an assumption and I'm
not going back on it :)

Thanks for making the two sides obviously clear!

cheers
James

-- 
-- James Mills
--
-- "Problems are solved by method"

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