summaryrefslogtreecommitdiff
path: root/perl/Git/SVN/Memoize/YAML.pm
diff options
context:
space:
mode:
Diffstat (limited to 'perl/Git/SVN/Memoize/YAML.pm')
-rw-r--r--perl/Git/SVN/Memoize/YAML.pm93
1 files changed, 93 insertions, 0 deletions
diff --git a/perl/Git/SVN/Memoize/YAML.pm b/perl/Git/SVN/Memoize/YAML.pm
new file mode 100644
index 0000000000..9676b8f2f7
--- /dev/null
+++ b/perl/Git/SVN/Memoize/YAML.pm
@@ -0,0 +1,93 @@
+package Git::SVN::Memoize::YAML;
+use warnings;
+use strict;
+use YAML::Any ();
+
+# based on Memoize::Storable.
+
+sub TIEHASH {
+ my $package = shift;
+ my $filename = shift;
+ my $truehash = (-e $filename) ? YAML::Any::LoadFile($filename) : {};
+ my $self = {FILENAME => $filename, H => $truehash};
+ bless $self => $package;
+}
+
+sub STORE {
+ my $self = shift;
+ $self->{H}{$_[0]} = $_[1];
+}
+
+sub FETCH {
+ my $self = shift;
+ $self->{H}{$_[0]};
+}
+
+sub EXISTS {
+ my $self = shift;
+ exists $self->{H}{$_[0]};
+}
+
+sub DESTROY {
+ my $self = shift;
+ YAML::Any::DumpFile($self->{FILENAME}, $self->{H});
+}
+
+sub SCALAR {
+ my $self = shift;
+ scalar(%{$self->{H}});
+}
+
+sub FIRSTKEY {
+ 'Fake hash from Git::SVN::Memoize::YAML';
+}
+
+sub NEXTKEY {
+ undef;
+}
+
+1;
+__END__
+
+=head1 NAME
+
+Git::SVN::Memoize::YAML - store Memoized data in YAML format
+
+=head1 SYNOPSIS
+
+ use Memoize;
+ use Git::SVN::Memoize::YAML;
+
+ tie my %cache => 'Git::SVN::Memoize::YAML', $filename;
+ memoize('slow_function', SCALAR_CACHE => [HASH => \%cache]);
+ slow_function(arguments);
+
+=head1 DESCRIPTION
+
+This module provides a class that can be used to tie a hash to a
+YAML file. The file is read when the hash is initialized and
+rewritten when the hash is destroyed.
+
+The intent is to allow L<Memoize> to back its cache with a file in
+YAML format, just like L<Memoize::Storable> allows L<Memoize> to
+back its cache with a file in Storable format. Unlike the Storable
+format, the YAML format is platform-independent and fairly stable.
+
+Carps on error.
+
+=head1 DIAGNOSTICS
+
+See L<YAML::Any>.
+
+=head1 DEPENDENCIES
+
+L<YAML::Any> from CPAN.
+
+=head1 INCOMPATIBILITIES
+
+None reported.
+
+=head1 BUGS
+
+The entire cache is read into a Perl hash when loading the file,
+so this is not very scalable.