Davide Bolcioni wrote:
> in the thread 'c++ wishlist', back in September, it was repeatedly
> asserted that no legal C++ expression can begin with a leading [.
>
> Assuming this is indeed the case, I am now wondering: is this also
> true for declarations ?

Yes.  A declaration cannot start with a [ token.

(The following is from memory, so the details may not be quite correct.
But I'm pretty sure that it is generally correct.)

A declaration consists of a decl-spec and one or more declarators.

A decl-spec can only contain a [ token if the [ token is within a
class/struct/union/enum definition or within template arguments.  In
both cases, it can't be at the beginning of the decl-spec.

A declarator can begin with a [ token, so we need to consider the case
where the decl-spec is empty, which means the declaration starts with
the declarator.  But (if I remember correctly) a decl-spec can only be
empty for declarations of constructors, destructors, and type conversion
operators.  And in those limited cases, the declarator must begin with a
qualified name (for out-of-class definitions) or with an identifier, ~
token, or operator keyword respectively (for in-class declarations).  So
a declarator that is preceded by an empty decl-spec cannot begin with a
[ token.

Therefore, a legal C++ declaration cannot start with a [ token.

--
David Olsen
qg4h9ykc5m@yahoo.com

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Greetings,
in the thread 'c++ wishlist', back in September, it was repeatedly
asserted that no legal C++ expression can begin with a leading [.

Assuming this is indeed the case, I am now wondering: is this also
true for declarations ?

Thank you for your consideration,
Davide Bolcioni
--
Paranoia is an afterthought.

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