Stephen Nelson-Smith wrote:
A friend of mine mentioned what he called the 'pythonic' idiom of:
print a or b
Isn't this a 'clever' kind or ternary - an if / else kind of thing?
I would say it's perfectly idiomatic in Python, but
not as a ternary. If you want a ternary use the
(relatively) recently-introduced:
a if <cond> else b
eg:
things = [1, 2 ,3]
print "%d thing%s found" % (len (things), "" if len (things) == 1 else "s")
Before this operator came along, people used to use
more-or-less clever-clever tricks with boolean operators
or using the fact that bool / int are interchangeable:
['s', ''][len (things) == 1]
The "a or b" idiom is most commonly used for default-type
situations:
def f (a, b=None):
print "a", b or "<Unknown>"
I don't warm to it... should I?
Up to you :) But I regard it as a useful idiom.
TJG
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