Rick Johnson於 2013年2月11日星期一UTC+8下午9時13分58秒寫道：
> On Monday, February 11, 2013 6:40:23 AM UTC-6, Chris Angelico wrote:
>
> > [...]
>
> > Or doing what you were pointing and laughing at Pike for, and using
>
> > two-symbol delimiters. You could even make it majorly logical:
>
> >
>
> > list_ = [[ 1, 2, 3 ]]
>
> > tuple_ = ([ 1, 2, 3 ])
>
> > dict_ = [{ 1, 2, 3 }]
>
> > frozendict_ = ({ 1, 2, 3 })
>
> > set_ = [< 1, 2, 3 >]
>
> > frozenset_ = (< 1, 2, 3 >)
>
>
>
> I am vehemently against using more than one "opening seq char" and one
> "closing seq char". It works fine for single depth sequences, however, once
> you start nesting the mental focus required to parse the doubled
> openers/closers is headache inducing. I would accept wrapping the literal in
> some sort of declaration though, something like i proposed earlier in the
> thread. The easiest is to use:
>
>
>
> set({1,2,3})
>
>
>
> but that looks like a function call! So we'd need a unique syntax. Either a
> single tag like:
>
>
>
> set{1,2,3}
>
>
>
> Or we could use start and end tags like:
>
>
>
> set{1,2,3}set
>
>
>
> where "set{" and "}set" are delimiters. For lists, tuples, and dict we would
> use the short form because these literals are far too ubiquitous:
>
>
>
> [1,2,3] # list
>
> {k:v} # dict
>
> (1,2,3) # tuple
>
>
>
> However, the grouping chars for tuples has always been confusing because they
> can clash with grouping of expressions. What is this?
>
>
>
> (1)
>
>
>
> It's NOT a tuple! But it looks like a tuple! What is this:
>
>
>
> 1,2
>
>
>
> it IS a tuple, but it does not look like a tuple!
>
>
>
> That's an unfortunate side effect of a poorly thought-out tuple syntax.
I am thinking a mutated list temporarily is useful when a list is to be used
to be iterated through all of its elements efficiently.
A permanently mutated list is a tuple of constant objects.
As for the set type, I prefer to use the operations of the list,
dictionaries in Python to act for the designed purposes.
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