Some syntactic sugar proposals

Dmitry Groshev lambdadmitry at gmail.com
Mon Nov 15 07:40:42 CET 2010


On Nov 15, 9:39 am, Dmitry Groshev <lambdadmi... at gmail.com> wrote:
> Here are some proposals. They are quite useful at my opinion and I'm
> interested for suggestions. It's all about some common patterns.
> First of all: how many times do you write something like
>     t = foo()
>     t = t if pred(t) else default_value
> ? Of course we can write it as
>     t = foo() if pred(foo()) else default_value
> but here we have 2 foo() calls instead of one. Why can't we write just
> something like this:
>     t = foo() if pred(it) else default_value
> where "it" means "foo() value"?
> Second, I saw a lot of questions about using dot notation for a
> "object-like" dictionaries and a lot of solutions like this:
>     class dotdict(dict):
>         def __getattr__(self, attr):
>             return self.get(attr, None)
>         __setattr__= dict.__setitem__
>         __delattr__= dict.__delitem__
> why there isn't something like this in a standart library?
> And the third. The more I use python the more I see how "natural" it
> can be. By "natural" I mean the statements like this:
>     [x.strip() for x in reversed(foo)]
> which looks almost like a natural language. But there is some
> pitfalls:
>     if x in range(a, b): #wrong!
> it feels so natural to check it that way, but we have to write
>     if a <= x <= b
> I understand that it's not a big deal, but it would be awesome to have
> some optimisations - it's clearly possible to detect things like that
> "wrong" one and fix it in a bytecode.
>
> x in range optimisation
> dot dict access
> foo() if foo() else bar()

Oh, I'm sorry. I forgot to delete my little notes at the bottom of
message.



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