Inline Conditionals?

[Joshua Ginsberg]

Is there any plan to include inline conditionals in Python? For example:

def isNegative(x):
return x < 0 ? True : False

Thanks!

-jag

--
Joshua Ginsberg <jo***@brainsto rminternet.net>
Brainstorm Internet Network Operations

[Adonis]

"Joshua Ginsberg" <jo***@brainsto rminternet.net> wrote in message
news:ma******** *************** *************** @python.org...

Is there any plan to include inline conditionals in Python? For example:

def isNegative(x):
return x < 0 ? True : False

Thanks!

-jag

--
Joshua Ginsberg <jo***@brainsto rminternet.net>
Brainstorm Internet Network Operations

How about something like:

def iif(condition, true=True, false=False): .... if condition:
.... return true
.... return false
.... iif('foo' == 'bar', 'w00t', 'l33t') 'l33t' iif('bar' == 'bar', 'w00t', 'l33t') 'w00t' iif('bar' == 'bar') True iif('foo' == 'bar') False

Hope this helps.

Adonis

[Chris Dutton]

Adonis wrote:

How about something like:

def iif(condition, true=True, false=False):

... if condition:
... return true
... return false
...

Just a thought, but this would have unexpected results if used with
function calls, if those function calls had side-effects, since both are
evaluated, whereas the ternary operator in other languages only
evaluates one of the possible expressions.

[Michael Hudson]

Joshua Ginsberg <jo***@brainsto rminternet.net> writes:

Is there any plan to include inline conditionals in Python? For example:

def isNegative(x):
return x < 0 ? True : False

Read PEP 308, and note that this was probably the largest flamewar in
Python history (well, before the still-ongoing decorators
discussion...).

But to answer your question: no.

Cheers,
mwh

--
Linux: Horse. Like a wild horse, fun to ride. Also prone to
throwing you and stamping you into the ground because it doesn't
like your socks. -- Jim's pedigree of operating systems, asr

[Peter Hansen]

Joshua Ginsberg wrote:

Is there any plan to include inline conditionals in Python? For example:

def isNegative(x):
return x < 0 ? True : False

This is a FAQ:
http://www.python.org/doc/faq/progra...rnary-operator

Newbies, please consider reading the several FAQs that you will find
at http://www.python.org/doc/faq/ before posting questions which
might be answered there (i.e. just about anything).

-Peter

[Alex Martelli]

Peter Hansen <pe***@engcorp. com> wrote:

Joshua Ginsberg wrote:

Is there any plan to include inline conditionals in Python? For example:

def isNegative(x):
return x < 0 ? True : False

This is a FAQ:

Newbies, please consider reading the several FAQs that you will find
at http://www.python.org/doc/faq/ before posting questions which
might be answered there (i.e. just about anything).

Peter's right. And Joshua's example shows how wise the BDFL was in
ruling out ternaries: sure, good programmers might occasionally have
found good uses for them, but we' have paid that with a LOT of horrid
code like that -- I've seen lots like that in C & its ilk, too.

return x < 0

on its own does EXACTLY the same job as the requested/wished-for

return x < 0 ? True : False

except is cleaner, clearer, faster, more concise, easier to read. So,
having a ternary operator would enable a little programming horror that
the lack of a ternary operator dissuades a little.

Of course, absit iniuria verbis, one cannot make anything foolproof,
because fools are SO ingenious -- I've also seen lots of code like:

if x < 0:
return True
else:
return False

which is, si licet es, even _worse_ than the wished-for ternary use!-)
Alex

[Antoon Pardon]

Op 2004-08-26, Alex Martelli schreef <al*****@yahoo. com>:

Peter Hansen <pe***@engcorp. com> wrote:

Joshua Ginsberg wrote:

> Is there any plan to include inline conditionals in Python? For example:
>
> def isNegative(x):
> return x < 0 ? True : False

This is a FAQ:

Newbies, please consider reading the several FAQs that you will find
at http://www.python.org/doc/faq/ before posting questions which
might be answered there (i.e. just about anything).

Peter's right. And Joshua's example shows how wise the BDFL was in
ruling out ternaries: sure, good programmers might occasionally have
found good uses for them, but we' have paid that with a LOT of horrid
code like that -- I've seen lots like that in C & its ilk, too.

When using list comprehension not having a ternary operator can be
a PITA. It is of course possible I miss something but how am I
supposed to do the following:

[ x.property ? foo(x) : bar(x) for x in Somelist ]

--
Antoon Pardon

[JCM]

Antoon Pardon <ap*****@forel. vub.ac.be> wrote:

Op 2004-08-26, Alex Martelli schreef <al*****@yahoo. com>: ....

Peter's right. And Joshua's example shows how wise the BDFL was in
ruling out ternaries: sure, good programmers might occasionally have
found good uses for them, but we' have paid that with a LOT of horrid
code like that -- I've seen lots like that in C & its ilk, too.

When using list comprehension not having a ternary operator can be
a PITA. It is of course possible I miss something but how am I
supposed to do the following: [ x.property ? foo(x) : bar(x) for x in Somelist ]

def foo_or_bar(x):
if x.property:
return foo(x)
return bar(x)

[foo_or_bar(x) for x in Somelist]
(still, I'd like to see a ternary conditional operator too...)

[John J. Lee]

al*****@yahoo.c om (Alex Martelli) writes:
[...]

Of course, absit iniuria verbis, one cannot make anything foolproof,
because fools are SO ingenious -- I've also seen lots of code like:

if x < 0:
return True
else:
return False

which is, si licet es, even _worse_ than the wished-for ternary use!-)

[...]

Argh.

I looked at that, and had a sinking feeling. I just found about ten
instances of that in my code!

Strange that, though I was innoculated against the general case of
this disease in the some years ago, I was apparently still entirely
susceptible to this particular strain of it.
John

[Alex Martelli]

Antoon Pardon <ap*****@forel. vub.ac.be> wrote:
...

When using list comprehension not having a ternary operator can be
a PITA. It is of course possible I miss something but how am I
supposed to do the following:

[ x.property ? foo(x) : bar(x) for x in Somelist ]

If you HAVE to use an LC by doctor's order, the above effect might be
obtained by coding something like:

[ (bar,foo)[bool(x.property )](x) for x in Somelist ]

If your physician should relent and let you code normal Python, though,

aux = []
for x in Somelist:
if x.property:
aux.append(foo( x))
else
aux.append(foo( x))

would be vastly more readable; "sparse is better than dense" and any LC
is far too dense to be Pythonic here.
Alex