104

do you know if Python supports some keyword or expression like in C++ to return values based on if condition, all in the same line (The C++ if expressed with the question mark ?)

// C++
value = ( a > 10 ? b : c )
Abruzzo Forte e Gentile
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    That C++ operator is called the "conditional operator" or the "ternary operator". –  Feb 03 '10 at 12:47

2 Answers2

167

From Python 2.5 onwards you can do:

value = b if a > 10 else c

Previously you would have to do something like the following, although the semantics isn't identical as the short circuiting effect is lost:

value = [c, b][a > 10]

There's also another hack using 'and ... or' but it's best to not use it as it has an undesirable behaviour in some situations that can lead to a hard to find bug. I won't even write the hack here as I think it's best not to use it, but you can read about it on Wikipedia if you want.

Mark Byers
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2

simple is the best and works in every version.

if a>10: 
    value="b"
else: 
    value="c"
ghostdog74
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