use strict; use warnings; package Data::OptList; # ABSTRACT: parse and validate simple name/value option pairs $Data::OptList::VERSION = '0.110'; use List::Util (); use Params::Util (); use Sub::Install 0.921 (); #pod =head1 SYNOPSIS #pod #pod use Data::OptList; #pod #pod my $options = Data::OptList::mkopt([ #pod qw(key1 key2 key3 key4), #pod key5 => { ... }, #pod key6 => [ ... ], #pod key7 => sub { ... }, #pod key8 => { ... }, #pod key8 => [ ... ], #pod ]); #pod #pod ...is the same thing, more or less, as: #pod #pod my $options = [ #pod [ key1 => undef, ], #pod [ key2 => undef, ], #pod [ key3 => undef, ], #pod [ key4 => undef, ], #pod [ key5 => { ... }, ], #pod [ key6 => [ ... ], ], #pod [ key7 => sub { ... }, ], #pod [ key8 => { ... }, ], #pod [ key8 => [ ... ], ], #pod ]); #pod #pod =head1 DESCRIPTION #pod #pod Hashes are great for storing named data, but if you want more than one entry #pod for a name, you have to use a list of pairs. Even then, this is really boring #pod to write: #pod #pod $values = [ #pod foo => undef, #pod bar => undef, #pod baz => undef, #pod xyz => { ... }, #pod ]; #pod #pod Just look at all those undefs! Don't worry, we can get rid of those: #pod #pod $values = [ #pod map { $_ => undef } qw(foo bar baz), #pod xyz => { ... }, #pod ]; #pod #pod Aaaauuugh! We've saved a little typing, but now it requires thought to read, #pod and thinking is even worse than typing... and it's got a bug! It looked right, #pod didn't it? Well, the C<< xyz => { ... } >> gets consumed by the map, and we #pod don't get the data we wanted. #pod #pod With Data::OptList, you can do this instead: #pod #pod $values = Data::OptList::mkopt([ #pod qw(foo bar baz), #pod xyz => { ... }, #pod ]); #pod #pod This works by assuming that any defined scalar is a name and any reference #pod following a name is its value. #pod #pod =func mkopt #pod #pod my $opt_list = Data::OptList::mkopt($input, \%arg); #pod #pod Valid arguments are: #pod #pod moniker - a word used in errors to describe the opt list; encouraged #pod require_unique - if true, no name may appear more than once #pod must_be - types to which opt list values are limited (described below) #pod name_test - a coderef used to test whether a value can be a name #pod (described below, but you probably don't want this) #pod #pod This produces an array of arrays; the inner arrays are name/value pairs. #pod Values will be either "undef" or a reference. #pod #pod Positional parameters may be used for compatibility with the old C<mkopt> #pod interface: #pod #pod my $opt_list = Data::OptList::mkopt($input, $moniker, $req_uni, $must_be); #pod #pod Valid values for C<$input>: #pod #pod undef -> [] #pod hashref -> [ [ key1 => value1 ] ... ] # non-ref values become undef #pod arrayref -> every name followed by a non-name becomes a pair: [ name => ref ] #pod every name followed by undef becomes a pair: [ name => undef ] #pod otherwise, it becomes [ name => undef ] like so: #pod [ "a", "b", [ 1, 2 ] ] -> [ [ a => undef ], [ b => [ 1, 2 ] ] ] #pod #pod By default, a I<name> is any defined non-reference. The C<name_test> parameter #pod can be a code ref that tests whether the argument passed it is a name or not. #pod This should be used rarely. Interactions between C<require_unique> and #pod C<name_test> are not yet particularly elegant, as C<require_unique> just tests #pod string equality. B<This may change.> #pod #pod The C<must_be> parameter is either a scalar or array of scalars; it defines #pod what kind(s) of refs may be values. If an invalid value is found, an exception #pod is thrown. If no value is passed for this argument, any reference is valid. #pod If C<must_be> specifies that values must be CODE, HASH, ARRAY, or SCALAR, then #pod Params::Util is used to check whether the given value can provide that #pod interface. Otherwise, it checks that the given value is an object of the kind. #pod #pod In other words: #pod #pod [ qw(SCALAR HASH Object::Known) ] #pod #pod Means: #pod #pod _SCALAR0($value) or _HASH($value) or _INSTANCE($value, 'Object::Known') #pod #pod =cut my %test_for; BEGIN { %test_for = ( CODE => \&Params::Util::_CODELIKE, ## no critic HASH => \&Params::Util::_HASHLIKE, ## no critic ARRAY => \&Params::Util::_ARRAYLIKE, ## no critic SCALAR => \&Params::Util::_SCALAR0, ## no critic ); } sub mkopt { my ($opt_list) = shift; my ($moniker, $require_unique, $must_be); # the old positional args my ($name_test, $is_a); if (@_) { if (@_ == 1 and Params::Util::_HASHLIKE($_[0])) { ($moniker, $require_unique, $must_be, $name_test) = @{$_[0]}{ qw(moniker require_unique must_be name_test) }; } else { ($moniker, $require_unique, $must_be) = @_; } # Transform the $must_be specification into a closure $is_a # that will check if a value matches the spec if (defined $must_be) { $must_be = [ $must_be ] unless ref $must_be; my @checks = map { my $class = $_; $test_for{$_} || sub { $_[1] = $class; goto \&Params::Util::_INSTANCE } } @$must_be; $is_a = (@checks == 1) ? $checks[0] : sub { my $value = $_[0]; List::Util::first { defined($_->($value)) } @checks }; $moniker = 'unnamed' unless defined $moniker; } } return [] unless $opt_list; $name_test ||= sub { ! ref $_[0] }; $opt_list = [ map { $_ => (ref $opt_list->{$_} ? $opt_list->{$_} : ()) } keys %$opt_list ] if ref $opt_list eq 'HASH'; my @return; my %seen; for (my $i = 0; $i < @$opt_list; $i++) { ## no critic my $name = $opt_list->[$i]; if ($require_unique) { Carp::croak "multiple definitions provided for $name" if $seen{$name}++; } my $value; if ($i < $#$opt_list) { if (not defined $opt_list->[$i+1]) { $i++ } elsif (! $name_test->($opt_list->[$i+1])) { $value = $opt_list->[++$i]; if ($is_a && !$is_a->($value)) { my $ref = ref $value; Carp::croak "$ref-ref values are not valid in $moniker opt list"; } } } push @return, [ $name => $value ]; } return \@return; } #pod =func mkopt_hash #pod #pod my $opt_hash = Data::OptList::mkopt_hash($input, $moniker, $must_be); #pod #pod Given valid C<L</mkopt>> input, this routine returns a reference to a hash. It #pod will throw an exception if any name has more than one value. #pod #pod =cut sub mkopt_hash { my ($opt_list, $moniker, $must_be) = @_; return {} unless $opt_list; $opt_list = mkopt($opt_list, $moniker, 1, $must_be); my %hash = map { $_->[0] => $_->[1] } @$opt_list; return \%hash; } #pod =head1 EXPORTS #pod #pod Both C<mkopt> and C<mkopt_hash> may be exported on request. #pod #pod =cut BEGIN { *import = Sub::Install::exporter { exports => [qw(mkopt mkopt_hash)], }; } 1; __END__ =pod =encoding UTF-8 =head1 NAME Data::OptList - parse and validate simple name/value option pairs =head1 VERSION version 0.110 =head1 SYNOPSIS use Data::OptList; my $options = Data::OptList::mkopt([ qw(key1 key2 key3 key4), key5 => { ... }, key6 => [ ... ], key7 => sub { ... }, key8 => { ... }, key8 => [ ... ], ]); ...is the same thing, more or less, as: my $options = [ [ key1 => undef, ], [ key2 => undef, ], [ key3 => undef, ], [ key4 => undef, ], [ key5 => { ... }, ], [ key6 => [ ... ], ], [ key7 => sub { ... }, ], [ key8 => { ... }, ], [ key8 => [ ... ], ], ]); =head1 DESCRIPTION Hashes are great for storing named data, but if you want more than one entry for a name, you have to use a list of pairs. Even then, this is really boring to write: $values = [ foo => undef, bar => undef, baz => undef, xyz => { ... }, ]; Just look at all those undefs! Don't worry, we can get rid of those: $values = [ map { $_ => undef } qw(foo bar baz), xyz => { ... }, ]; Aaaauuugh! We've saved a little typing, but now it requires thought to read, and thinking is even worse than typing... and it's got a bug! It looked right, didn't it? Well, the C<< xyz => { ... } >> gets consumed by the map, and we don't get the data we wanted. With Data::OptList, you can do this instead: $values = Data::OptList::mkopt([ qw(foo bar baz), xyz => { ... }, ]); This works by assuming that any defined scalar is a name and any reference following a name is its value. =head1 FUNCTIONS =head2 mkopt my $opt_list = Data::OptList::mkopt($input, \%arg); Valid arguments are: moniker - a word used in errors to describe the opt list; encouraged require_unique - if true, no name may appear more than once must_be - types to which opt list values are limited (described below) name_test - a coderef used to test whether a value can be a name (described below, but you probably don't want this) This produces an array of arrays; the inner arrays are name/value pairs. Values will be either "undef" or a reference. Positional parameters may be used for compatibility with the old C<mkopt> interface: my $opt_list = Data::OptList::mkopt($input, $moniker, $req_uni, $must_be); Valid values for C<$input>: undef -> [] hashref -> [ [ key1 => value1 ] ... ] # non-ref values become undef arrayref -> every name followed by a non-name becomes a pair: [ name => ref ] every name followed by undef becomes a pair: [ name => undef ] otherwise, it becomes [ name => undef ] like so: [ "a", "b", [ 1, 2 ] ] -> [ [ a => undef ], [ b => [ 1, 2 ] ] ] By default, a I<name> is any defined non-reference. The C<name_test> parameter can be a code ref that tests whether the argument passed it is a name or not. This should be used rarely. Interactions between C<require_unique> and C<name_test> are not yet particularly elegant, as C<require_unique> just tests string equality. B<This may change.> The C<must_be> parameter is either a scalar or array of scalars; it defines what kind(s) of refs may be values. If an invalid value is found, an exception is thrown. If no value is passed for this argument, any reference is valid. If C<must_be> specifies that values must be CODE, HASH, ARRAY, or SCALAR, then Params::Util is used to check whether the given value can provide that interface. Otherwise, it checks that the given value is an object of the kind. In other words: [ qw(SCALAR HASH Object::Known) ] Means: _SCALAR0($value) or _HASH($value) or _INSTANCE($value, 'Object::Known') =head2 mkopt_hash my $opt_hash = Data::OptList::mkopt_hash($input, $moniker, $must_be); Given valid C<L</mkopt>> input, this routine returns a reference to a hash. It will throw an exception if any name has more than one value. =head1 EXPORTS Both C<mkopt> and C<mkopt_hash> may be exported on request. =head1 AUTHOR Ricardo Signes <rjbs@cpan.org> =head1 CONTRIBUTORS =for stopwords Olivier Mengué Ricardo SIGNES =over 4 =item * Olivier Mengué <dolmen@cpan.org> =item * Ricardo SIGNES <rjbs@codesimply.com> =back =head1 COPYRIGHT AND LICENSE This software is copyright (c) 2006 by Ricardo Signes. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. =cut