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Comment by ronnix | Hacker News Reader

You can have a one-line "if" statement [1]:

  if a == 42: print "Yes" ; do_stuff()

It's true that you cannot have a "else" statement on the same line, however.

But in some cases, you could use a conditional expression instead [2]:

  x = f() if a == 42 else g()

[1] http://docs.python.org/reference/compound_stmts.html

[2] http://docs.python.org/reference/expressions.html#conditiona...

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in this case plain old C syntax is much more readable:

x = (a==42) ? f() : g();

In this case I think the PEP8 spacing guidelines are counterproductive:

    f() if a==42 else g()

looks much more readable to me than

    f() if a == 42 else g()

I think that it's much more readable due to familiarity more than anything else. The C syntax for the ternary operator was the one thing that it took me the longest time to get used to when learning to program. I usually just ignored it because it was too hard to remember what it did. That said, I can easily read it now, but I still feel that the Python syntax is more understandable.

Which is more readable:

  > condition ? value1 : value2

  > value1 if condition else value2

Maybe the latter is just more readable to me because I'm used to reading Perl all day long that looks like:

  > die unless condition;
  > return true if condition;
  > return false
  >     if condition1 && condition2 && condition3;

That said, I'm also used to reading:

  > return condition1   ? value1
  >        : condition2 ? value2
  >        : condition3 ? value3
  >                     : value4;

and I still find the Python ternary operator more readable:

  > return value1 if condition1 else
  >        value2 if condition2 else
  >        value3 if condition3 else
  >        value4

Personally, I still have to think about what the ternary operator means every time I see it. It's just so nonobvious.

You can also write it this way, which is more similar to C:

  x = (a==42) and f() or g()

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