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Re: Zen of Python
On Tue, 28 May 2002, Fredrik Lundh wrote:
> Avi Bryant wrote:
> > What's the equivalent Python idiom?
> d.setdefault("spam", 42)
Not the same thing at all, unless you happen to be using a constant value.
Perhaps my example should have been
d at: 'spam' ifAbsentPut: [x * 42]
> if d.has_key("spam"):
> d["spam"] = 42
I assume you mean "unless", not "if". Nothing much wrong with this, I
agree, but it's a statement, not an expression. The argument will be that
having to use extra temps is never bad because it always makes things more
readable anyway, which I don't necessarily agree with, but fair enough.
> or, if you insist:
> if_absent_put(d, "spam", lambda: 42)
Actually I'd prefer d.at("spam", if_absent_put=lambda: 42). Which is a
shame because it doesn't correspond nicely to the  operator. Is
d["spam", if_absent_put=lambda:42] legal?
But that's clearly not actually idiomatic Python. This is a discussion
about culture as much as anything, isn't it?
> > My guess is that it will be either less regular, or less explicit,
> > or both.
Whatever indeed. This whole thread is turning into a language pissing
match. Count me out.