.\" ident	@(#)G2++:g2++lib/man/Vblock.3	3.2
.\"
.\" C++ Standard Components, Release 3.0.
.\"
.\" Copyright (c) 1991, 1992 AT&T and UNIX System Laboratories, Inc.
.\" Copyright (c) 1988, 1989, 1990 AT&T.  All Rights Reserved.
.\"
.\" THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF AT&T and UNIX System
.\" Laboratories, Inc.  The copyright notice above does not evidence
.\" any actual or intended publication of such source code.
.\" 
.TH \f3Vblock\fP \f3G2++(3C++)\fP " "
.SH NAME
Vblock \- Similar to Block
.SH SYNOPSIS OF Vblock.h
.Bf

    template <class \*(gt> class Vblock{
    public:

	//  similar to Block(3C++)

    };

.Be
.SH DESCRIPTION
.PP
A Vblock is just like a Block (see \f3Block(3C++)\f1), 
except that (for technical
reasons having to do with G2++) some of its member 
functions are virtual.  If a G2++ record definition
(see \f3G2++(4C++)\f1) specifies an array, 
the corresponding declaration generated
by \f3g2++comp(1C++)\f1 in the \f4.h\f1 file will 
contain a Vblock (see the \f3EXAMPLE\f1).
.SH EXAMPLE
When compiled by \f3g2++comp(1C++)\f1, the following
record definition
.Bf

    \fIusr.g\fP

	usr
		name	*
		proj
			*(100)	LONG


.Be
generates a \f4.h\f1 file containing the following:
.Bf

    \fIusr.h\fP

	...

	typedef struct USR{
		String	name;
		Vblock<LONG>	proj;
		USR();
	}USR;

.Be
A client program may manipulate the \f4proj\f1
field just as though it were a Block, e.g.,
.Bf

	#include "usr.h"
	main(){

	    USR u;

	    for(int i=0;i<100;i++){
		u.proj.reserve(i);
		u.proj[i] = i;
	    }
	}
.Be
.SH SEE ALSO
.Bf
\f3Block(3C++)\f1
\f3g2++comp(1C++)\f1
\f3typed_io(G2++(3C++))\f1
.Be