Python ternary conditional operator

The ternary operator x=(y>x)?y:z  is rather convenient and is widely used by programmer. Python got its own idiosyncratic variant only in version 2.5.

I find the Python variant slightly misguided. It looks to me as an extension if Perl postfix if operator -- a questionable construct in its own right.

No only because it’s different from the C ternary syntax )which is standard de-factor for this construct and withstood the test of time), but because (1) the order of the terms doesn’t match the logical ordering that first we do the test and then we look at one of the outcomes. And (2) it’s nice to be able to compare the two alternatives ‘side by side’ without having to ‘skip over’ something in between.

consider these:

perl:

print ( $i != 0 ) ? ( $i ) : "zero\n";

print $i if ( i != 3 ) else "zero\n" 
                 

The fact that it does not  start with condition look unnatural, and amateurish.  Like is the case with Perl postfix if, this is not a one step forward two steps back. Perl postfix if  still can be useful with the next and last statements (continue and break in Python), while Python variant is not.

This solution also can be viewed as a typical illustration on NIH syndrome.

Old News ;-)

[Nov 14, 2019] I'm annoyed with Python's ternary operator by Brian

July 2, 2013 | pythontesting.net

46 Comments

The ternary operator is a way to concisely say:

"If test , then a , else b ",

with the value of the statement being the value of a or b .

language	how to say it
C	test ? a : b
C++	test ? a : b
javaScript	test ? a : b
Perl (not perl 6)	test ? a : b
PHP	test ? a : b
Ruby	test ? a : b
Julia	test ? a : b
Did I forget some language?	probably
Python	a if test else b Why??

Why??

Ok. Now that I've written this post, I'll remember it.

However, I just want to say on behalf of all of the other multiple-language programmers in the world, THIS IS LAME!!!

Joe , July 2, 2013 at 4:11 pm

All those languages essentially copied it from the granddaddy (i.e., C). Also, the ternary operator (properly called "conditional expressions") are a relatively recent addition to Python (2.5) and from what I heard Guido resisted adding it.

And the BDFL also didn't copy other C features, e.g., increment/decrement operators, || and && for Boolean operations, switch/case statements, and not least: BRACES!!! (for scope, of course).

Craig , July 2, 2013 at 7:16 pm

To be fair, I find the inconsistency to be a little jarring too. While a lot of python flows nicely this jars; and working across multiple languages is one of those oddities you need to remember for apparently no good reason.

[Nov 12, 2019] c - python (conditional-ternary) operator for assignments

Nov 12, 2019 | stackoverflow.com

python ? (conditional/ternary) operator for assignments [duplicate] Ask Question Asked 9 years, 4 months ago Active 5 years, 3 months ago Viewed 55k times 88 8

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This question already has an answer here:

• Does Python have a ternary conditional operator? 23 answers

karadoc ,May 14, 2013 at 13:01

Python has such an operator:

variable = something if condition else something_else

Alternatively, although not recommended (see @karadoc's comment):

variable = (condition and something) or something_else

Will ,Jul 30, 2014 at 9:01

In older Python code, you may see the trick:

condition and something or something_else

however, this has been superseded by the vastly superior ... if ... else ... construct:

something if condition else something_else

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