Re: list <T>::iterator _it ; fails to compile

[Jonathan Wakely <cow at compsoc dot man dot ac dot uk>]

On Fri, Aug 13, 2004 at 02:36:01PM +0200, Arnaud Gardelein wrote:

> Hello !
> 
>   It seems that when I try to create a list iterator in a template class
> with "list<T>::iterator _it ;", gcc-3.4.0 does not like that, whereas
> version 3.2.2 does (compilation details follows) :
> 
> gcc-3.4.0 :
> test.cpp:9: error: expected `;' before "_it"
> 
> gcc-3.2.2 :
> test.cpp:9: warning: `typename std::list<T, std::allocator<_CharT>
> >::iterator' is implicitly a typename
> test.cpp:9: warning: implicit typename is deprecated, please see the
> documentation for details
> 
>   What's wrong ?

GCC 3.3.2 tells you what's wrong with the code and tells you to check
the docs to understand it.  If you'd fixed the code to remove the
warning it would have made it compile with 3.4

The implicit typename feature that was deprecated in 3.3 was removed
from 3.4, so the code is no longer accepted.

You need to say "typename" before referring to a type that is dependent
on a template parameter, to tell the compiler that the name refers to
a type and not something else (such as a variable or a function).


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