+Hash tied to record all the accessed keys.

diff --git a/Hash/Makefile.am b/Hash/Makefile.am
index 7a7d772..e1e05a3 100644 (file)
--- a/Hash/Makefile.am
+++ b/Hash/Makefile.am
@@ -22,5 +22,6 @@ EXTRA_DIST+= \
                Push.pm \
                Sub.pm \
                Readonly.pm \
-               RestrictTo.pm
+               RestrictTo.pm \
+               RecordKeys.pm
 

diff --git a/Hash/RecordKeys.pm b/Hash/RecordKeys.pm
new file mode 100644 (file)
index 0000000..653c5a2
--- /dev/null
+++ b/Hash/RecordKeys.pm
@@ -0,0 +1,114 @@
+# $Id$
+# Hash tied to record all the accessed keys.
+# Copyright (C) 2005 Jan Kratochvil <project-www.jankratochvil.net@jankratochvil.net>
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; exactly version 2 of June 1991 is required
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+
+package My::Hash::RecordKeys;
+our $VERSION=do { my @r=(q$Revision$=~/\d+/g); sprintf "%d.".("%03d"x$#r),@r; };
+our $CVS_ID=q$Id$;
+use strict;
+use warnings;
+use My::Web;   # for &Wrequire
+Wrequire 'My::Hash';
+our @ISA=qw(My::Hash);
+use Carp qw(cluck confess);
+
+
+sub TIEHASH($$)
+{
+my($class,$parent)=@_;
+
+       my $self=$class->SUPER::TIEHASH($parent);
+       $self->{"keyshash"}={};
+       return $self;
+}
+
+# Call as: my @accessed=tied(%$ref)->accessed();
+sub accessed($)
+{
+my($self)=@_;
+
+       return keys(%{$self->{"keyshash"}})
+}
+
+sub STORE($$$)
+{
+my($this,$key,$value)=@_;
+
+       $this->{"keyshash"}{$key}=1;
+       return $this->pass("STORE",$key,$value);
+}
+
+sub FETCH($$)
+{
+my($this,$key)=@_;
+
+       $this->{"keyshash"}{$key}=1;
+       return $this->pass("FETCH",$key);
+}
+
+sub FIRSTKEY($)
+{
+my($this)=@_;
+
+       my $a=keys(%{$this->{"parent"}});
+       return $this->NEXTKEY($this,undef());
+}
+
+sub NEXTKEY($$)
+{
+my($this,$lastkey)=@_;
+
+cluck "TODO: Enumeration may not be expected.";
+       for (;;) {
+               my $key=each(%{$this->{"parent"}});
+               return if !defined $key;
+               $this->{"keyshash"}{$key}=1;
+               return $key 
+               }
+}
+
+sub EXISTS($$)
+{
+my($this,$key)=@_;
+
+       $this->{"keyshash"}{$key}=1;
+       return $this->pass("EXISTS",$key);
+}
+
+sub DELETE($$)
+{
+my($this,$key)=@_;
+
+       $this->{"keyshash"}{$key}=1;
+       return $this->pass("DELETE",$key);
+}
+
+sub CLEAR($)
+{
+my($this)=@_;
+
+confess "TODO: Not implementable.";
+}
+
+sub SCALAR
+{
+my($this)=@_;
+
+confess "TODO: Not yet implemented.";
+}
+
+1;