[Python-Dev] (try-except) conditional expression similar to (if-else) conditional (PEP 308) (original) (raw)

Stephen J. Turnbull stephen at xemacs.org
Sat Aug 8 15:19:23 CEST 2009

Steven D'Aprano writes:

It's not immediately obvious to me why the last expression should be given that privileged rule. Why not the first expression?

Or the second, for that matter. So find a large body of Lisp code and run "grep -r prog1 | wc", "grep -r prog2 | wc", and "grep -r progn | wc" on it. I think the pragmatic answer will be obvious.

Personally, I like functional languages and style. But I admit the need for a progn construct (ie, "block") to express procedural style, and see no particular reason why expressing that by making a syntactic distinction between expressions and statements is worse (or better) than the progn construct. That should be kept distinct from the question of whether extended assignment operators or conditional operators are appropriate for a given language.

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