Py3K idea: why not drop the colon?

Ron Adam rrr at ronadam.com
Fri Nov 10 20:01:06 CET 2006


Michael Hobbs wrote:

> The same problem that is solved by not having to type parens around the 
> 'if' conditional, a la C and its derivatives. That is, it's unnecessary 
> typing to no good advantage, IMHO. I was coding in Ruby for several 
> months and got very comfortable with just typing the if conditional and 
> hitting return, without any extra syntax. When I came back to Python, I 
> found that I felt annoyed every time I typed the colon, since it 
> obviously isn't required. The FAQ says that the colon increases 
> readability, but I'm skeptical. The indentation seems to provide more 
> than enough of a visual clue as to where the if conditional ends.

I'm not sure why '\'s are required to do multi-line before the colon.  Possibly 
because if multi-line conditional expressions are the norm, dropping a colon 
could result in valid (but incorrect) code instead of an error?

The faq also pointed out a technical reason for requiring the colon.  It makes 
the underlying parser much easier to write and maintain.  This shouldn't be 
taken to lightly in my opinion, because a simpler easer to maintain and more 
reliable python parser means development time can be spent improving the 
language in other areas instead of fixing parsing problems every time a new 
feature is added that might be used in a conditional expression.

Cheers,
    Ron













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