.TH "FBB::Reverse" "3bobcat" "2005\-2023" "libbobcat\-dev_6\&.04\&.00" "for\-loop reverse iterators"

.PP 
.SH "NAME"
FBB::Reverse \- A class template offering reverse iterators
.PP 
.SH "SYNOPSIS"
\fB#include <bobcat/reverse>\fP
.br 

.PP 
.SH "DESCRIPTION"

.PP 
Not all data types offering (or implicitly providing) iterators also offer
\fIreverse_iterators\fP\&. Arrays don\(cq\&t, and neither do
\fIinitalizer_lists\fP\&. Pointers to array elements can be used instead of
iterators, but arrays cannot be used in range\-based for\-loops\&. The \fIRanger\fP
class (cf\&. \fBranger\fP(3bobcat)) can be used for defining \fIbegin\fP and \fIend\fP
members allowing the use of arrays in range\-based for\-loops\&. Using \fBReverse\fP
objects and data structures can be used in range\-based for\-loops and/or to
obtain reverse\-iterators to visit data elements in reversed order\&.
.PP 
The class template \fIReverse, ReverseArray,\fP and \fIReverseSize\fP are
normally not directly used, but are returned by the various \fIreverse\fP
support functions\&. These three classes offer two members \fIbegin\fP, returning
a \fIreverse_iterator\fP to the end of the data range of the object passed to
\fIreverse\fP and \fIend\fP returning a \fIreverse_iterator\fP to the beginning of
the data range of the object passed to \fIreverse\fP\&.
.PP 
.SH "NAMESPACE"
\fBFBB\fP
.br 
All constructors, members, operators and manipulators, mentioned in this
man\-page, are defined in the namespace \fBFBB\fP\&.
.PP 
.SH "INHERITS FROM"
\-
.PP 
.SH "REVERSE FUNCTIONS"
.IP o 
\fBreverse(Type &object)\fP:
.br 
returns a \fIReverse\fP object offering reverse iterators to the data
range of \fIobject\fP, which must support \fIbegin\fP and \fIend\fP
members\&. If \fIType\fP is a constant type, then \fIReverse\(cq\&s begin\fP and \fIend\fP
members return \fIconst_reverse_iterators\fP, otherwise \fIreverse_iterators\fP
are returned;
.IP 
.IP o 
\fBreverse(Type (&array)[size])\fP:
.br 
returns a \fIReverse\fP object offering reverse iterators to the
reversed range of elements of \fIarray\fP\&. If \fIType\fP is a constant type, then
\fIReverse\(cq\&s begin\fP and \fIend\fP members return \fIconst_reverse_iterators\fP,
otherwise \fIreverse_iterators\fP are returned;
.IP 
.IP o 
\fBreverse(Type *array, size_t size)\fP:
.br 
returns a \fIReverse\fP object offering reverse iterators to the
reversed range of elements of \fIarray\fP to \fIarray + size\fP\&. If \fIType\fP is a
constant type, then \fIReverse\(cq\&s begin\fP and \fIend\fP members return
\fIconst_reverse_iterators\fP, otherwise \fIreverse_iterators\fP are returned\&.
.SH "EXAMPLE"
.nf 
#include <iostream>
#include <vector>

#include <bobcat/reverse>

using namespace std;
using namespace FBB;

int main()
{
    int intArr[] = { 1, 2, 3, 4, 5};        // arrays of known sizes
    for (int value: reverse(intArr))
        cout << value << \(cq\& \(cq\&;
    cout << \(cq\&\en\(cq\&;

    for (int value: reverse(intArr, 5))     // using specified sizes
        cout << value << \(cq\& \(cq\&;
    cout << \(cq\&\en\(cq\&;

    int const constArr[] = { 1, 2, 3, 4, 5};// arrays with const elements
    for (int value: reverse(constArr))
        cout << value << \(cq\& \(cq\&;
    cout << \(cq\&\en\(cq\&;

    for (int value: reverse(constArr, 5))   // using specified sizes
        cout << value << \(cq\& \(cq\&;
    cout << \(cq\&\en\(cq\&;

    for (int value: reverse(intArr, 5))     // arrays of specified sizes
        cout << value << \(cq\& \(cq\&;
    cout << \(cq\&\en\(cq\&;


    vector<int> vi{ 1, 2, 3, 4, 5 };        // handle non\-const objects
    for (int value: reverse(vi))
        cout << value << \(cq\& \(cq\&;
    cout << \(cq\&\en\(cq\&;

    vector<int> const cvi{ 1, 2, 3, 4, 5 }; // handle const objects
    for (int value: reverse(cvi))
        cout << value << \(cq\& \(cq\&;
    cout << \(cq\&\en\(cq\&;
                                            // handle lvalues
    for (int value: reverse(initializer_list<int>{ 1, 2, 4, 8 }))
        cout << value << \(cq\& \(cq\&;
    cout\&.put(\(cq\&\en\(cq\&);
                                            // named constant objects
    auto ilist = initializer_list<int>{ 1, 2, 4, 8 };
    for (int value: reverse(ilist))
        cout << value << \(cq\& \(cq\&;
    cout\&.put(\(cq\&\en\(cq\&);
}

.fi 

.PP 
.SH "FILES"
\fIbobcat/reverse\fP \- defines the class interfaces and declares the
\fIreverse\fP functions\&.
.PP 
.SH "SEE ALSO"
\fBbobcat\fP(7), \fBranger\fP(3bobcat)
.PP 
.SH "BUGS"
None Reported\&.
.PP 
.SH "BOBCAT PROJECT FILES"

.PP 
.IP o 
\fIhttps://fbb\-git\&.gitlab\&.io/bobcat/\fP: gitlab project page;
.IP o 
\fIbobcat_6\&.04\&.00\-x\&.dsc\fP: detached signature;
.IP o 
\fIbobcat_6\&.04\&.00\-x\&.tar\&.gz\fP: source archive;
.IP o 
\fIbobcat_6\&.04\&.00\-x_i386\&.changes\fP: change log;
.IP o 
\fIlibbobcat1_6\&.04\&.00\-x_*\&.deb\fP: debian package containing the
libraries;
.IP o 
\fIlibbobcat1\-dev_6\&.04\&.00\-x_*\&.deb\fP: debian package containing the
libraries, headers and manual pages;

.PP 
.SH "BOBCAT"
Bobcat is an acronym of `Brokken\(cq\&s Own Base Classes And Templates\(cq\&\&.
.PP 
.SH "COPYRIGHT"
This is free software, distributed under the terms of the
GNU General Public License (GPL)\&.
.PP 
.SH "AUTHOR"
Frank B\&. Brokken (\fBf\&.b\&.brokken@rug\&.nl\fP)\&.
.PP