NAME Bitmask::Data - Handle unlimited length bitmasks in an easy and flexible way SYNOPSIS # Create a simple bitmask class package MyBitmask; use base qw(Bitmask::Data); __PACKAGE__->bitmask_length(18); __PACKAGE__->bitmask_default('0b000000000000000011'); __PACKAGE__->init( 'value1' => '0b000000000000000001', 'value2' => '0b000000000000000010', 'value2' => '0b000000000000000100', 'value4' => '0b000000000000001000', 'value5' => '0b000000000000010000', ... ); ## Somewhere else in your code use MyBitmask; my $bm1 = MyBitmask->new('value1','value3'); my $bm2 = MyBitmask->new('0b000000000000010010'); $bm1->add('value3'); my $bm3 = $bm1 | $bm2; $bm3->string; DESCRIPTION This package helps you dealing with bitmasks. First you need to subclass Bitmask::Data and set the bitmask values and length. (If you are only working with a single bitmask in a simple application you might also initialize the bitmask directly in the Bitmask::Data module). After the initialization you can create an arbitrary number of bitmask objects which can be accessed and manipulated with convenient methods and overloaded arithmetic and bit operators. Bitmask::Data does not store bitmasks as integers internally, but as strings conststing of \0 and \1, hence makinging unlimited length bitmasks possible (32-bit perl can handle integer bitmasks only up to 40 bits). METHODS Class Methods bitmask_length Set/Get the length of the bitmask. Do not change this value after the initialization. Bitmask length is unlimited. Default: 16 bitmask_default Set/Get the default bitmask for empty Bitmask::Data objects. Default: undef bitmask_lazyinit If true value that disables warnings for lazy initialization. (Lazy initialization = call of init without bitmask bit values). Default: 0 __PACKAGE__->bitmask_lazyinit(1); __PACKAGE__->bitmask_length(6); __PACKAGE__->init( 'value1', # will be 0b000001 'value2', # will be 0b000010 'value3' # will be 0b000100 ); If bitmask_lazyinit is 2 then bit values will be filled from left to right, otherwise from right to left __PACKAGE__->bitmask_lazyinit(2); __PACKAGE__->bitmask_length(6); __PACKAGE__->init( 'value1', # will be 0b100000 'value2', # will be 0b010000 'value3' # will be 0b001000 ); bitmask_items HASHREF of all bitmask items, with values as keys and bitmask as values. init CLASS->init(LIST of VALUES); Initializes the bitmask class. You can supply a list of possible values. Optionally you can also specify the bits for the mask by adding bit values after the value. CLASS->init( 'value1' => 0b000001, 'value2' => 0b000010, 'value3' => 0b001000, 'value4' => 0b010000, ); With "bitmask_lazyinit" enabled you can also skip the bitmask bit values CLASS->bitmask_lazyinit(1); CLASS->init( 'value1', 'value2', 'value3', 'value4', ); Bits may be supplied as integers, strings or Math::BigInt objects (not recommended). CLASS->init( 'value1' => 0b000001, # integer 'value2' => 2, # integer 'value3' => '0b000100' # string starting with '0b' 'value4' => '0B001000' # string starting with '0B' 'value5' => '\0\1\0\0\0\0' # string consisting of \0 and \1 'value6' => Math::BigInt->new("32") # Math::BigInt object ); int2bit my $bitmask_string = CLASS->int2bit(INTEGER); Helper method that turns an integer into the internal bitmask representation string2bit my $bitmask_string = CLASS->string2bit(STRING); Helper method that takes a string like '0B001010' or '0b010101' and turns it into the internal bitmask representation any2bitmask my $bitmask_string = CLASS->any2bitmask(ANYTHING); Helper method that tries to turn a data into the internal bitmask representation. This method can hanle * any Bitmask::Data object * Math::BigInt object * a string matching on of the bitmask values * a bitmask string consisting of \0 and \1 characters * a bitmask string starting with '0b' or '0B' and containing only 0 and 1 * an integer _parse_params my $bitmask_string = CLASS->_parse_params(LIST) Helper method for parsing params passed to various methods. Overloaded operators Bitmask::Data uses overload by default. * Numeric context Returns bitmask integer value (see integer method). For large bitmasks (> 40 bits) this will allways be a Math::BigInt object (hence using this method is not recommended). * Scalar context Returns bitmask string representation (see string method) * ==, eq, <=>, cmp Works like 'has_any' * Smartmatch Works like has_any. $bm = new Somebitmask->new('v1','v2'); $bm ~~ ['v1','v3'] # true, because 'v1' matches even if 'v3' is not set * +, - Adds/Removes bits to/from the bitmask without changing the current object. The result is returned as a new Bitmask::Data object. * -=, += Adds/Removes bits to/from the current bitmask object. * ~, ^, &, | Performs the bitwise operations without changing the current object. The result is returned as a new Bitmask::Data object. * ^=, &=, |= Performs the bitwise operations on the current bitmask object. Constructors new my $bm = MyBitmask->new(); my $bm = MyBitmask->new('value1'); my $bm = MyBitmask->new('0b00010000010000'); my $bm = MyBitmask->new(124); my $bm = MyBitmask->new(0b00010000010000); my $bm = MyBitmask->new(0x2); my $bm = MyBitmask->new($another_bm_object); my $bm = MyBitmask->new("\0\1\0\0\1"); my $bm = MyBitmask->new('value2', 'value3'); my $bm = MyBitmask->new([32, 'value1', 0b00010000010000]); Create a new bitmask object. You can supply almost any combination of ARRAYREFS, bits, Bitmask::Data objects, Math::BigInt objects, bitmasks and values, even mix different types. See any2bitmask for details on possible formats. new_from_bitmask my $bm = MyBitmask->new_from_bitmask($bitmask_string); Create a new bitmask object from a bitmask string (as returned by many helper methods). Public Methods clone my $bm_new = $bm->clone(); Clones an existing Bitmask::Data object and. set $bm->set(PARAMS); This methpd resets the current bitmask and sets the supplied arguments. Takes the same arguments as "new". Returns the object. remove $bm->remove(PARAMS) Removes the given values/bits from the bitmask. Takes the same arguments as "new". Returns the object. add $bm->add(PARAMS) Adds the given values/bits to the bitmask. Takes the same arguments as "new". Returns the object. reset $bm->reset() Resets the bitmask to the default (or empty) bitmask. Returns the object. set_all $bm->set_all() Sets all defined bits in the bitmask. Returns the object. neg $bm->neg() Negates/Inverts the bitmask Returns the object. list my @values = $bm->list(); OR my $values = $bm->list(); In list context, this returns a list of the set values in scalar context, this returns an array reference to the list of values. length my $length = $bm->length(); Number of set bitmask values. first my $value = $bm->first() Returns the first set value. The order is determined by the bit value. integer my $integer = $bm->integer(); Returns the bitmask as an integer. For bitmasks with a length > 40 this will always be a Math::BigInt object. string my $string = $bm->string(); Returns the bitmask as a string of 0 and 1. bitmask my $string = $bm->bitmask(); Returns the bitmask in the internal representation: A string of \0 and \1 sqlfilter_all This method can be used for database searches in conjunction with SQL::Abstract an POSTGRESQL (SQL::Abstract is used by DBIx::Class for generating searches). The search will find all database rows with bitmask that have at least the given values set. (use the "sql" method for an exact match) Example how to use sqlfilter with SQL::Abstract: my($stmt, @bind) = $sql->select( 'mytable', \@fields, { $bm->sqlfilter_all('mytable.bitmaskfield'), } ); Example how to use sqlfilter with DBIx::Class: my $list = $resultset->search( { $bm->sqlfilter_all('me.bitmaskfield'), }, ); sqlfilter_any Works like "sqlfilter_all" but checks for any bit matching sqlstring Returns the bitmask as a quoted string as needed by PostgreSQL: B'0000000000000001'::bit(16) has_all if ($bm->has_all(PARAMS)) { # Do something } Checks if all requestes bits/values are set and returns true or false. This method takes the same arguments as "new". has_exact if ($bm->has_exact(PARAMS)) { # Do something } Checks if the set bits/values excactly match the supplied bits/values and returns true or false. This method takes the same arguments as "new". has_any if ($bm->has_any(PARAMS)) { # Do something } Checks if at least one set value/bit matches the supplied bits/values and returns true or false. This method takes the same arguments as "new". CAVEATS Since Bitmask::Data is very liberal with input data you cannot use numbers as bitmask values. (It would think that you are supplying an integer bitmask and not a value) Bitmask::Data adds a considerable processing overhead to bitmask manipulations. If you either don't need the extra comfort or use bitmasks with less that 40 bits that you should consider using just the perl built in bit operators on simple integer values. SUBCLASSING Bitmask::Data was designed to be subclassed. package MyBitmask; use parent qw(Bitmask::Data); __PACKAGE__->bitmask_length(20); # Default length is 16 __PACKAGE__->init( 'value1' => 0b000000000000000001, 'value2' => 0x2, 'value2' => 4, 'value4', # lazy initlialization 'value5', # lazy initlialization ); WORKING WITH DATABASES This module comes with support for POSTGRESQL databases (patches for other database vendors are welcome). First you need to create the correct column types: CREATE TABLE bitmaskexample ( id integer DEFAULT nextval('pkey_seq'::regclass) NOT NULL, bitmask bit(14), otherfields character varying ); The length of the bitmask field must match "CLASS->bitmask_length". This module provides three convenient methods to work with databases: * sqlfilter_all: Search for matching bitmasks * sqlfilter_any: Search for bitmasks with matching bits * string: Print the bitmask string as used by the database If you are working with l you might also install de- and inflators for Bitmask::Data objects: __PACKAGE__->inflate_column('fieldname',{ inflate => sub { my $value = shift; return MyBitmask->new($value); }, deflate => sub { my $value = shift; undef $value unless ref($value) && $value->isa('MyBitmask'); $value //= MyBitmask->new(); return $value->string; }, }); SUPPORT Please report any bugs or feature requests to "bug-bitmask-data@rt.cpan.org", or through the web interface at . I will be notified and then you'll automatically be notified of the progress on your report as I make changes. AUTHOR Klaus Ita koki [at] worstofall.com Maroš Kollár CPAN ID: MAROS maros [at] k-1.com L ACKNOWLEDGEMENTS This module was originally written by Klaus Ita (Koki) for Revdev , a nice litte software company I (Maros) run with Koki and Domm (). COPYRIGHT & LICENSE Bitmask::Data is Copyright (c) 2008 Klaus Ita, Maroš Kollár - This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of the license can be found in the LICENSE file included with this module.