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Subject: Re: [std-discussion] Re: An implementation of Generic
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2013/1/12 Andrea Proli <andy.prowl@gmail.com>:
> I was used to think of lambdas as syntactic sugar, but *generic* lambdas are
> not: the generated closure breaks the rule from paragraph 14/2:
>
> "A template-declaration can appear only as a namespace scope or class scope
> declaration".
>
> I am unaware of the reasons why this restriction exists in the first place
> (I did some research but with no success), so I cannot write a proposal on
> lifting it. However, if good reasons exist, I am curious whether the fact
> that generic lambdas break it will create troubles.

Polymorphic (or generic, if you prefer) lambda expressions don't
provide the full capacities of templates. As you say, they just are
syntactic sugar for some sub-space of possible template constructions.
It is therefore much simpler to add them compared to starting with a
support for local templates from begin with. This would not
necessarily result in a conflict with 14/2, you just add one
exceptional rule and that's it.

- Daniel

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