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

This solution also can be viewed as

 


Top Visited
Switchboard
Latest
Past week
Past month

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


This question already has an answer here:

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

Recommended Links

Google matched content

Softpanorama Recommended

Top articles

Sites

One line if statement in Python (ternary conditional operator) - Python Central



Etc

Society

Groupthink : Two Party System as Polyarchy : Corruption of Regulators : Bureaucracies : Understanding Micromanagers and Control Freaks : Toxic Managers :   Harvard Mafia : Diplomatic Communication : Surviving a Bad Performance Review : Insufficient Retirement Funds as Immanent Problem of Neoliberal Regime : PseudoScience : Who Rules America : Neoliberalism  : The Iron Law of Oligarchy : Libertarian Philosophy

Quotes

War and Peace : Skeptical Finance : John Kenneth Galbraith :Talleyrand : Oscar Wilde : Otto Von Bismarck : Keynes : George Carlin : Skeptics : Propaganda  : SE quotes : Language Design and Programming Quotes : Random IT-related quotesSomerset Maugham : Marcus Aurelius : Kurt Vonnegut : Eric Hoffer : Winston Churchill : Napoleon Bonaparte : Ambrose BierceBernard Shaw : Mark Twain Quotes

Bulletin:

Vol 25, No.12 (December, 2013) Rational Fools vs. Efficient Crooks The efficient markets hypothesis : Political Skeptic Bulletin, 2013 : Unemployment Bulletin, 2010 :  Vol 23, No.10 (October, 2011) An observation about corporate security departments : Slightly Skeptical Euromaydan Chronicles, June 2014 : Greenspan legacy bulletin, 2008 : Vol 25, No.10 (October, 2013) Cryptolocker Trojan (Win32/Crilock.A) : Vol 25, No.08 (August, 2013) Cloud providers as intelligence collection hubs : Financial Humor Bulletin, 2010 : Inequality Bulletin, 2009 : Financial Humor Bulletin, 2008 : Copyleft Problems Bulletin, 2004 : Financial Humor Bulletin, 2011 : Energy Bulletin, 2010 : Malware Protection Bulletin, 2010 : Vol 26, No.1 (January, 2013) Object-Oriented Cult : Political Skeptic Bulletin, 2011 : Vol 23, No.11 (November, 2011) Softpanorama classification of sysadmin horror stories : Vol 25, No.05 (May, 2013) Corporate bullshit as a communication method  : Vol 25, No.06 (June, 2013) A Note on the Relationship of Brooks Law and Conway Law

History:

Fifty glorious years (1950-2000): the triumph of the US computer engineering : Donald Knuth : TAoCP and its Influence of Computer Science : Richard Stallman : Linus Torvalds  : Larry Wall  : John K. Ousterhout : CTSS : Multix OS Unix History : Unix shell history : VI editor : History of pipes concept : Solaris : MS DOSProgramming Languages History : PL/1 : Simula 67 : C : History of GCC developmentScripting Languages : Perl history   : OS History : Mail : DNS : SSH : CPU Instruction Sets : SPARC systems 1987-2006 : Norton Commander : Norton Utilities : Norton Ghost : Frontpage history : Malware Defense History : GNU Screen : OSS early history

Classic books:

The Peter Principle : Parkinson Law : 1984 : The Mythical Man-MonthHow to Solve It by George Polya : The Art of Computer Programming : The Elements of Programming Style : The Unix Hater’s Handbook : The Jargon file : The True Believer : Programming Pearls : The Good Soldier Svejk : The Power Elite

Most popular humor pages:

Manifest of the Softpanorama IT Slacker Society : Ten Commandments of the IT Slackers Society : Computer Humor Collection : BSD Logo Story : The Cuckoo's Egg : IT Slang : C++ Humor : ARE YOU A BBS ADDICT? : The Perl Purity Test : Object oriented programmers of all nations : Financial Humor : Financial Humor Bulletin, 2008 : Financial Humor Bulletin, 2010 : The Most Comprehensive Collection of Editor-related Humor : Programming Language Humor : Goldman Sachs related humor : Greenspan humor : C Humor : Scripting Humor : Real Programmers Humor : Web Humor : GPL-related Humor : OFM Humor : Politically Incorrect Humor : IDS Humor : "Linux Sucks" Humor : Russian Musical Humor : Best Russian Programmer Humor : Microsoft plans to buy Catholic Church : Richard Stallman Related Humor : Admin Humor : Perl-related Humor : Linus Torvalds Related humor : PseudoScience Related Humor : Networking Humor : Shell Humor : Financial Humor Bulletin, 2011 : Financial Humor Bulletin, 2012 : Financial Humor Bulletin, 2013 : Java Humor : Software Engineering Humor : Sun Solaris Related Humor : Education Humor : IBM Humor : Assembler-related Humor : VIM Humor : Computer Viruses Humor : Bright tomorrow is rescheduled to a day after tomorrow : Classic Computer Humor

The Last but not Least Technology is dominated by two types of people: those who understand what they do not manage and those who manage what they do not understand ~Archibald Putt. Ph.D


Copyright © 1996-2020 by Softpanorama Society. www.softpanorama.org was initially created as a service to the (now defunct) UN Sustainable Development Networking Programme (SDNP) without any remuneration. This document is an industrial compilation designed and created exclusively for educational use and is distributed under the Softpanorama Content License. Original materials copyright belong to respective owners. Quotes are made for educational purposes only in compliance with the fair use doctrine.

FAIR USE NOTICE This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available to advance understanding of computer science, IT technology, economic, scientific, and social issues. We believe this constitutes a 'fair use' of any such copyrighted material as provided by section 107 of the US Copyright Law according to which such material can be distributed without profit exclusively for research and educational purposes.

This is a Spartan WHYFF (We Help You For Free) site written by people for whom English is not a native language. Grammar and spelling errors should be expected. The site contain some broken links as it develops like a living tree...

You can use PayPal to to buy a cup of coffee for authors of this site

Disclaimer:

The statements, views and opinions presented on this web page are those of the author (or referenced source) and are not endorsed by, nor do they necessarily reflect, the opinions of the Softpanorama society. We do not warrant the correctness of the information provided or its fitness for any purpose. The site uses AdSense so you need to be aware of Google privacy policy. You you do not want to be tracked by Google please disable Javascript for this site. This site is perfectly usable without Javascript.

Last modified: July 28, 2020