Issue 1971:  Extraction of strings from an Any (cxx_revision)
Source:  (, )
Nature:  Uncategorized Issue
Severity: 
Summary: Summary: What happens if I write
 
 	CORBA::Any a = ...;
 	const char *p;
 
 	a >>= p;
 
 and the type code in the Any indicates a *bounded* string? Does the extraction
 succeed or fail? The mapping doesn"t say.
 
 

Resolution: 
Revised Text: 
Actions taken:
September 17, 1998: received issue
Discussion: 
deferred in June 2011 to the next RTF
End of Annotations:=====
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Date: Thu, 17 Sep 1998 11:43:26 +1000 (EST)
From: Michi Henning <michi@dstc.edu.au>
To: issues@omg.org, cxx_revision@omg.org
Subject: Extraction of strings from an Any

What happens if I write

	CORBA::Any a = ...;
	const char *p;

	a >>= p;

and the type code in the Any indicates a *bounded* string? Does the
extraction
succeed or fail? The mapping doesn't say.

According to the new TypeCode::equivalent section, the extraction
should fail, because it says that when extracting from an Any,
equivalent()
determines success of failure.

The problem I have is that I think it would be easier for the above
extraction
to succeed because the C++ mapping forces me to deal with bounded
strings
as char * throughout. In particular, without a generic extraction for
strings, I can't easily pass a string<10> that I receive from one
place
as a string<20> to another operation, even though the string value
fits.

I think we should decide what to do here and specify the behavior.

							Cheers,

								Michi.
--
Michi Henning              +61 7 33654310
DSTC Pty Ltd               +61 7 33654311 (fax)
University of Qld 4072     michi@dstc.edu.au
AUSTRALIA
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Date: Mon, 28 May 2001 14:50:04 +1000 (EST)
From: Michi Henning <michi.henning@iona.com>
Reply-To: C++ Revision Task Force <cxx_revision@omg.org>
To: C++ Revision Task Force <cxx_revision@omg.org>
Subject: Proposal for 1971
Message-ID: <Pine.HPX.4.05.10105281442500.1568-100000@bobo.ooc.com.au>
Organization: IONA Technologies
MIME-Version: 1.0
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Status: RO

While it would be nice to be able to generically extract and insert
bounded strings via (const) char *, the feature isn't essential. So,
in essence, I'd like to close the issue without adding the new
feature.

However, the spec doesn't say what the behavior should be if the bound
value doesn't match for extraction, so I think we should add a
sentence for
clarification.

Proposal:

Insert the following para in 1.16.4, following the para beginning with
"A bound value of zero passed to the appropriate helper type...":

   For successful extraction of bounded strings with to_string, the
   bound value supplied to the constructor must match the bound
   in the Any's TypeCode; otherwise, the constructor fails and
   subsequent extraction with operator>>= returns false.

							Cheers,

														Michi.
--
Michi Henning                             +61 7 3324 9633
Chief CORBA Scientist                     +61 4 1118 2700 (mobile)
IONA Technologies                         +61 7 3324 9799 (fax)
Total Business Integration
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