The ternary operator in Python

The ? : operator that you may have come across in Perl, PHP, C and Java - known as the ternary or conditional operator - is ABSENT from Python. "But it's so useful" I hear you cry. Ah yes, but isn't this elegant:

val = float(raw_input("Age: "))
status = ("working","retired")[val>65]
print "You should be",status

UPDATE ... There IS now a "ternary" operator in Python (recent versions of Python 2, and Python 3) ... this post was orginally made in March 2006 ...

Footnote - the ? : operator in those other languages gives you a very convening short form of if, then, else where you can select a value based on a condition for printing or assigning to a variable; here's a Perl or PHP example:

$status = ($val > 65) ? "retired" : "working";

Great, useful, but yet another oddball structure on the language - I'm forever having to explain how an operator can have three operands and how you MUST have a : if you have a ? ... but in Python it's so natural to use a tuple ...

(written 2006-03-25 17:18:24)

Associated topics are indexed under

H104 - PHP - Control Statements
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  [1825] Question Mark - Colon operator (Perl and PHP) - (2008-10-08)
  [1696] Saying NOT in Perl, PHP, Python, Lua ... - (2008-07-04)
  [1477] Decisions - small ones, or big ones? - (2007-12-18)
  [1220] for loop - how it works (Perl, PHP, Java, C, etc) - (2007-06-06)
  [1199] Testing for one of a list of values. - (2007-05-22)
  [1191] Smart English Output - via PHP and Perl ? : operator - (2007-05-18)
  [962] Breaking a loop - Ruby and other languages - (2006-12-03)
  [863] Double and Triple equals operator in PHP - (2006-09-12)
  [421] Don't repeat code - use loops or functions - (2005-08-21)
  [406] Assignment, equality and identity in PHP - (2005-08-08)
  [353] Wimbledon Neck - (2005-06-20)
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P206 - Perl - More Loops and Conditionals
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  [299] What - no switch or case statement? - (2005-05-03)
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Y103 - Python - Conditionals and Loops
  [1661] Equality, sameness and identity - Python - (2008-05-31)
  [1201] No switch in Python - (2007-05-23)
  [909] Python is like a narrowboat - (2006-10-30)
  [835] Python - when to use the in operator - (2006-08-16)
  [788] New - Conditional expressions in Python 2.5 - (2006-07-01)
  [668] Python - block insets help with documentation - (2006-04-04)

Y104 - Python - Lists and Tuples
  [2368] Python - fresh examples of all the fundamentals - (2009-08-20)
  [2284] Strings as collections in Python - (2009-07-12)
  [2280] Creating and iterating through Python lists - (2009-07-12)
  [1789] Looking for a value in a list - Python - (2008-09-08)
  [1641] Tektronix 4010 series / Python Tuples - (2008-05-13)
  [955] Python collections - mutable and imutable - (2006-11-29)
  [899] Python - extend v append on a list - (2006-10-20)
  [383] Overloading of operators on standard objects in Python - (2005-07-19)

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