[Python-ideas] PEP 505 (None coalescing operators) thoughts
steve at pearwood.info
Mon Sep 28 18:37:33 CEST 2015
On Mon, Sep 28, 2015 at 06:11:45PM +0200, Sven R. Kunze wrote:
> That sums it all up for me as well, though I would rather use "else"
> instead of "or?" (see punctuation-heavy).
`else` is ambiguous. Consider:
result = spam if eggs else cheese else aardvark
could be interpreted three ways:
result = (spam if eggs else cheese) else aardvark
result = spam if (eggs else cheese) else aardvark
result = spam if eggs else (cheese else aardvark)
Whichever precedence you pick, some people will get it wrong and it will
silently do the wrong thing and lead to hard-to-diagnose bugs. Using
"else" for this will be a bug-magnet.
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