Re: attempting template metaprog to print arbitrary container

From:
Alan Johnson <alanwj@no.spam.stanford.edu>
Newsgroups:
comp.lang.c++
Date:
Fri, 12 May 2006 17:42:22 -0700
Message-ID:
<e43a1e$bsn$1@news.Stanford.EDU>
tutufan@gmail.com wrote:

It seems like this is close to a solution, but the g++ doesn't like it
(error at bottom). Any suggestions?

[snip]

1094: error: explicit specialization in non-namespace scope 'struct
debug_print_container<T, Dim>'
1094: error: enclosing class templates are not explicitly specialized
1095: error: template parameters not used in partial specialization:
1095: error: 'T'
1095: error: 'Dim'


You are trying to explicitly specialize a member template without
explicitly specializing its enclosing templates, which is not allowed.
See 14.7.3.18 of the standard:

"In an explicit specialization declaration for a member of a class
template or a member template that appears in namespace scope, the
member template and some of its enclosing class templates may remain
unspecialized, except that the declaration shall not explicitly
specialize a class member template if its enclosing class templates are
not explicitly specialized as well."

There is probably a good reason why such a thing is not allowed, but I
don't know it.

--
Alan Johnson

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