.\" Automatically generated by Pod::Man 4.14 (Pod::Simple 3.43)
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
..
.de Vb \" Begin verbatim text
.ft CW
.nf
.ne \\$1
..
.de Ve \" End verbatim text
.ft R
.fi
..
.\" Set up some character translations and predefined strings.  \*(-- will
.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
.\" double quote, and \*(R" will give a right double quote.  \*(C+ will
.\" give a nicer C++.  Capital omega is used to do unbreakable dashes and
.\" therefore won't be available.  \*(C` and \*(C' expand to `' in nroff,
.\" nothing in troff, for use with C<>.
.tr \(*W-
.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
.ie n \{\
.    ds -- \(*W-
.    ds PI pi
.    if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
.    if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\"  diablo 12 pitch
.    ds L" ""
.    ds R" ""
.    ds C` ""
.    ds C' ""
'br\}
.el\{\
.    ds -- \|\(em\|
.    ds PI \(*p
.    ds L" ``
.    ds R" ''
.    ds C`
.    ds C'
'br\}
.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD.  Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.\"
.\" Avoid warning from groff about undefined register 'F'.
.de IX
..
.nr rF 0
.if \n(.g .if rF .nr rF 1
.if (\n(rF:(\n(.g==0)) \{\
.    if \nF \{\
.        de IX
.        tm Index:\\$1\t\\n%\t"\\$2"
..
.        if !\nF==2 \{\
.            nr % 0
.            nr F 2
.        \}
.    \}
.\}
.rr rF
.\" ========================================================================
.\"
.IX Title "Class::Adapter::Clear 3pm"
.TH Class::Adapter::Clear 3pm "2022-12-04" "perl v5.36.0" "User Contributed Perl Documentation"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
Class::Adapter::Clear \- A handy base Adapter class that makes no changes
.SH "VERSION"
.IX Header "VERSION"
version 1.09
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
\&\fBHello World with \s-1CGI\s0.pm the normal way\fR
.PP
.Vb 3
\&  # Load and create the CGI
\&  use CGI;
\&  $q = new CGI;
\&  
\&  # Create the page
\&  print $q\->header,                    # HTTP Header
\&        $q\->start_html(\*(Aqhello world\*(Aq), # Start the page
\&        $q\->h1(\*(Aqhello world\*(Aq),         # Hello World!
\&        $q\->end_html;                  # End the page
.Ve
.PP
\&\fBHello World with \s-1CGI\s0.pm the Adapter'ed way\fR
.PP
.Vb 3
\&  # Load and create the CGI
\&  use CGI;
\&  $q = new CGI;
\&  
\&  # Convert to an Adapter
\&  use Class::Adapter::Clear;
\&  $q = new Class::Adapter::Clear( $q );
\&  
\&  # Create the page
\&  print $q\->header,                    # HTTP Header
\&        $q\->start_html(\*(Aqhello world\*(Aq), # Start the page
\&        $q\->h1(\*(Aqhello world\*(Aq),         # Hello World!
\&        $q\->end_html;                  # End the page
.Ve
.PP
\&\fBCreating a \s-1CGI\s0 Adapter class using Class::Adapter::Clear\fR
.PP
.Vb 1
\&  package My::CGI;
\&  
\&  use base \*(AqClass::Adapter::Clear\*(Aq;
\&  
\&  # Optional \- Create the thing we are decorating auto\-magically
\&  sub new {
\&      my $class = shift;
\&  
\&      # Create the object we are decorating
\&      my $query = CGI\->new(@_);
\&  
\&      # Wrap it in the Adapter
\&      $class\->SUPER::new($query);
\&  }
\&  
\&  # Decorate the h1 method to change what is created
\&  sub h1 {
\&        my $self = shift;
\&        my $str  = shift;
\&  
\&    # Do something before the real method call
\&    if ( defined $str and $str eq \*(Aqhello world\*(Aq ) {
\&        $str = \*(AqHello World!\*(Aq;
\&    }
\&    
\&    $self\->_OBJECT_\->($str, @_);
\&  }
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\f(CW\*(C`Class::Adapter::Clear\*(C'\fR provides the base class for creating one common
type of Class::Adapter classes. For more power, move up to
Class::Adapter::Builder.
.PP
On it's own \f(CW\*(C`Class::Adapter::Clear\*(C'\fR passes all methods through to the same
method in the parent object with the same parameters, responds to
\&\f(CW\*(C`\->isa\*(C'\fR like the parent object, and responds to \f(CW\*(C`\->can\*(C'\fR like
the parent object.
.PP
It looks like a \f(CW\*(C`Duck\*(C'\fR, and it quacks like a \f(CW\*(C`Duck\*(C'\fR.
.PP
On this base, you simple implement whatever method you want to do
something special to.
.PP
.Vb 5
\&  # Different method, same parameters
\&  sub method1 {
\&      my $self = shift;
\&      $self\->_OBJECT_\->method2(@_); # Call a different method
\&  }
\&  
\&  # Same method, different parameters
\&  sub method1 {
\&      my $self = shift;
\&      $self\->_OBJECT_\->method1( lc($_[0]) ); # Lowercase the param
\&  }
\&  
\&  # Same method, same parameters, tweak the result
\&  sub method1 {
\&      my $self = shift;
\&      my $rv = $self\->_OBJECT_\->method1(@_);
\&      $rv =~ s/\en/<br>\en/g; # Add line\-break HTML tags at each newline
\&      return $rv;
\&  }
.Ve
.PP
As you can see, the advantage of this full-scale \fIAdapter\fR approach,
compared to inheritance, or function wrapping (see Class::Hook), is
that you have complete and utter freedom to do anything you might need
to do, without stressing the Perl inheritance model or doing anything
unusual or tricky with \f(CW\*(C`CODE\*(C'\fR references.
.PP
You may never need this much power. But when you need it, you \fBreally\fR
need it.
.PP
As an aside, Class::Adapter::Clear is implemented with the following
Class::Adapter::Builder formula.
.PP
.Vb 3
\&  use Class::Adapter::Builder
\&      ISA      => \*(Aq_OBJECT_\*(Aq,
\&      AUTOLOAD => 1;
.Ve
.SH "METHODS"
.IX Header "METHODS"
.ie n .SS "new $object"
.el .SS "new \f(CW$object\fP"
.IX Subsection "new $object"
As does the base Class::Adapter class, the default \f(CW\*(C`new\*(C'\fR constructor
takes a single object as argument and creates a new object which holds the
passed object.
.PP
Returns a new \f(CW\*(C`Class::Adapter::Clear\*(C'\fR object, or \f(CW\*(C`undef\*(C'\fR if you do not pass
in an object.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
Class::Adapter, Class::Adapter::Builder
.SH "SUPPORT"
.IX Header "SUPPORT"
Bugs may be submitted through the \s-1RT\s0 bug tracker <https://rt.cpan.org/Public/Dist/Display.html?Name=Class-Adapter>
(or bug\-Class\-Adapter@rt.cpan.org <mailto:bug-Class-Adapter@rt.cpan.org>).
.SH "AUTHOR"
.IX Header "AUTHOR"
Adam Kennedy <adamk@cpan.org>
.SH "COPYRIGHT AND LICENSE"
.IX Header "COPYRIGHT AND LICENSE"
This software is copyright (c) 2005 by Adam Kennedy.
.PP
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.