view release on metacpan or  search on metacpan

lib/AnyDBM_File/Importer.pm  view on Meta::CPAN

our $VERSION = '0.012';

=head1 AnyDBM_File::Importer - Import DBM package symbols when using AnyDBM_File

=head1 SYNOPSIS

 BEGIN {
    @AnyDBM_File::ISA = qw( DB_File SDBM_File ) unless @AnyDBM_File::ISA;
 }
 use AnyDBM_File;
 use vars qw( $DB_BTREE &R_DUP); # must declare the globals you expect to use
 use AnyDBM_File::Importer qw(:bdb); # an import tag is REQUIRED

 my %db;
 $DB_BTREE->{'flags'} = R_DUP;
 tie( %db, 'AnyDBM_File', O_CREAT | O_RDWR, 0644, $DB_BTREE);

=head1 DESCRIPTION

This module allows symbols (like $DB_HASH, R_DUP, etc.) to be
imported into the caller's namespace when using the L<AnyDBM_File> DBM

lib/AnyDBM_File/Importer.pm  view on Meta::CPAN

This is essentially a hack because it relies on L<AnyDBM_File>
internal behavior. Specifically, at the time of DBM module selection,
C<AnyDBM_File> sets its C<@ISA> to a length 1 array containing the
package name of the selected DBM module.

=head1 USAGE NOTES

Use of L<AnyDBM_File::Importer> within module code currently requires
a kludge.  Symbols of imported variables or constants need to be
declared globals, as in the SYNOPSIS above. This is not necessary when
L<AnyDBM_File::Importer> is used in package main. Better solutions are hereby solicited with advance gratitude.

L<AnyDBM_File::Importer> consists entirely of an import function. To
import the symbols, a tag must be given. More than one tag can be
supplied. Symbols cannot be individually specified at the moment.

 :bdb    DB_File (BDB) symbols ($DB_*, R_*, O_*)
 :db     $DB_* type hashrefs
 :R      R_* constants (R_DUP, R_FIRST, etc)
 :O      O_* constants (O_CREAT, O_RDWR, etc)