| 1 | # autoconf -- create `configure' using m4 macros
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| 2 | # Copyright (C) 2001, 2002 Free Software Foundation, Inc.
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| 3 |
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| 4 | # This program is free software; you can redistribute it and/or modify
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| 5 | # it under the terms of the GNU General Public License as published by
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| 6 | # the Free Software Foundation; either version 2, or (at your option)
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| 7 | # any later version.
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| 8 |
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| 9 | # This program is distributed in the hope that it will be useful,
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| 10 | # but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 11 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 12 | # GNU General Public License for more details.
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| 13 |
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| 14 | # You should have received a copy of the GNU General Public License
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| 15 | # along with this program; if not, write to the Free Software
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| 16 | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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| 17 | # 02110-1301, USA.
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| 18 |
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| 19 | # This file is basically Perl 5.6's Class::Struct, but made compatible
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| 20 | # with Perl 5.5. If someday this has to be updated, be sure to rename
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| 21 | # all the occurrences of Class::Struct into Automake::Struct, otherwise
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| 22 | # if we `use' a Perl module (e.g., File::stat) that uses Class::Struct,
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| 23 | # we would have two packages defining the same symbols. Boom.
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| 24 |
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| 25 | package Automake::Struct;
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| 26 |
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| 27 | ## See POD after __END__
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| 28 |
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| 29 | use 5.005_03;
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| 30 |
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| 31 | use strict;
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| 32 | use vars qw(@ISA @EXPORT $VERSION);
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| 33 |
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| 34 | use Carp;
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| 35 |
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| 36 | require Exporter;
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| 37 | @ISA = qw(Exporter);
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| 38 | @EXPORT = qw(struct);
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| 39 |
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| 40 | $VERSION = '0.58';
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| 41 |
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| 42 | ## Tested on 5.002 and 5.003 without class membership tests:
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| 43 | my $CHECK_CLASS_MEMBERSHIP = ($] >= 5.003_95);
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| 44 |
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| 45 | my $print = 0;
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| 46 | sub printem {
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| 47 | if (@_) { $print = shift }
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| 48 | else { $print++ }
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| 49 | }
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| 50 |
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| 51 | {
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| 52 | package Automake::Struct::Tie_ISA;
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| 53 |
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| 54 | sub TIEARRAY {
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| 55 | my $class = shift;
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| 56 | return bless [], $class;
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| 57 | }
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| 58 |
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| 59 | sub STORE {
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| 60 | my ($self, $index, $value) = @_;
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| 61 | Automake::Struct::_subclass_error();
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| 62 | }
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| 63 |
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| 64 | sub FETCH {
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| 65 | my ($self, $index) = @_;
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| 66 | $self->[$index];
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| 67 | }
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| 68 |
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| 69 | sub FETCHSIZE {
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| 70 | my $self = shift;
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| 71 | return scalar(@$self);
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| 72 | }
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| 73 |
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| 74 | sub DESTROY { }
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| 75 | }
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| 76 |
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| 77 | sub struct {
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| 78 |
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| 79 | # Determine parameter list structure, one of:
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| 80 | # struct( class => [ element-list ])
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| 81 | # struct( class => { element-list })
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| 82 | # struct( element-list )
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| 83 | # Latter form assumes current package name as struct name.
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| 84 |
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| 85 | my ($class, @decls);
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| 86 | my $base_type = ref $_[1];
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| 87 | if ( $base_type eq 'HASH' ) {
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| 88 | $class = shift;
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| 89 | @decls = %{shift()};
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| 90 | _usage_error() if @_;
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| 91 | }
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| 92 | elsif ( $base_type eq 'ARRAY' ) {
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| 93 | $class = shift;
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| 94 | @decls = @{shift()};
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| 95 | _usage_error() if @_;
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| 96 | }
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| 97 | else {
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| 98 | $base_type = 'ARRAY';
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| 99 | $class = (caller())[0];
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| 100 | @decls = @_;
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| 101 | }
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| 102 | _usage_error() if @decls % 2 == 1;
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| 103 |
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| 104 | # Ensure we are not, and will not be, a subclass.
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| 105 |
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| 106 | my $isa = do {
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| 107 | no strict 'refs';
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| 108 | \@{$class . '::ISA'};
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| 109 | };
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| 110 | _subclass_error() if @$isa;
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| 111 | tie @$isa, 'Automake::Struct::Tie_ISA';
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| 112 |
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| 113 | # Create constructor.
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| 114 |
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| 115 | croak "function 'new' already defined in package $class"
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| 116 | if do { no strict 'refs'; defined &{$class . "::new"} };
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| 117 |
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| 118 | my @methods = ();
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| 119 | my %refs = ();
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| 120 | my %arrays = ();
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| 121 | my %hashes = ();
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| 122 | my %classes = ();
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| 123 | my $got_class = 0;
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| 124 | my $out = '';
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| 125 |
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| 126 | $out = "{\n package $class;\n use Carp;\n sub new {\n";
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| 127 | $out .= " my (\$class, \%init) = \@_;\n";
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| 128 | $out .= " \$class = __PACKAGE__ unless \@_;\n";
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| 129 |
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| 130 | my $cnt = 0;
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| 131 | my $idx = 0;
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| 132 | my( $cmt, $name, $type, $elem );
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| 133 |
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| 134 | if( $base_type eq 'HASH' ){
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| 135 | $out .= " my(\$r) = {};\n";
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| 136 | $cmt = '';
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| 137 | }
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| 138 | elsif( $base_type eq 'ARRAY' ){
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| 139 | $out .= " my(\$r) = [];\n";
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| 140 | }
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| 141 | while( $idx < @decls ){
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| 142 | $name = $decls[$idx];
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| 143 | $type = $decls[$idx+1];
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| 144 | push( @methods, $name );
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| 145 | if( $base_type eq 'HASH' ){
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| 146 | $elem = "{'${class}::$name'}";
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| 147 | }
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| 148 | elsif( $base_type eq 'ARRAY' ){
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| 149 | $elem = "[$cnt]";
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| 150 | ++$cnt;
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| 151 | $cmt = " # $name";
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| 152 | }
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| 153 | if( $type =~ /^\*(.)/ ){
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| 154 | $refs{$name}++;
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| 155 | $type = $1;
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| 156 | }
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| 157 | my $init = "defined(\$init{'$name'}) ? \$init{'$name'} :";
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| 158 | if( $type eq '@' ){
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| 159 | $out .= " croak 'Initializer for $name must be array reference'\n";
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| 160 | $out .= " if defined(\$init{'$name'}) && ref(\$init{'$name'}) ne 'ARRAY';\n";
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| 161 | $out .= " \$r->$elem = $init [];$cmt\n";
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| 162 | $arrays{$name}++;
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| 163 | }
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| 164 | elsif( $type eq '%' ){
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| 165 | $out .= " croak 'Initializer for $name must be hash reference'\n";
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| 166 | $out .= " if defined(\$init{'$name'}) && ref(\$init{'$name'}) ne 'HASH';\n";
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| 167 | $out .= " \$r->$elem = $init {};$cmt\n";
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| 168 | $hashes{$name}++;
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| 169 | }
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| 170 | elsif ( $type eq '$') {
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| 171 | $out .= " \$r->$elem = $init undef;$cmt\n";
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| 172 | }
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| 173 | elsif( $type =~ /^\w+(?:::\w+)*$/ ){
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| 174 | $init = "defined(\$init{'$name'}) ? \%{\$init{'$name'}} : ()";
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| 175 | $out .= " croak 'Initializer for $name must be hash reference'\n";
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| 176 | $out .= " if defined(\$init{'$name'}) && ref(\$init{'$name'}) ne 'HASH';\n";
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| 177 | $out .= " \$r->$elem = '${type}'->new($init);$cmt\n";
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| 178 | $classes{$name} = $type;
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| 179 | $got_class = 1;
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| 180 | }
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| 181 | else{
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| 182 | croak "'$type' is not a valid struct element type";
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| 183 | }
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| 184 | $idx += 2;
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| 185 | }
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| 186 | $out .= " bless \$r, \$class;\n }\n";
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| 187 |
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| 188 | # Create accessor methods.
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| 189 |
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| 190 | my( $pre, $pst, $sel );
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| 191 | $cnt = 0;
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| 192 | foreach $name (@methods){
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| 193 | if ( do { no strict 'refs'; defined &{$class . "::$name"} } ) {
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| 194 | carp "function '$name' already defined, overrides struct accessor method";
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| 195 | }
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| 196 | else {
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| 197 | $pre = $pst = $cmt = $sel = '';
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| 198 | if( defined $refs{$name} ){
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| 199 | $pre = "\\(";
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| 200 | $pst = ")";
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| 201 | $cmt = " # returns ref";
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| 202 | }
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| 203 | $out .= " sub $name {$cmt\n my \$r = shift;\n";
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| 204 | if( $base_type eq 'ARRAY' ){
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| 205 | $elem = "[$cnt]";
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| 206 | ++$cnt;
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| 207 | }
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| 208 | elsif( $base_type eq 'HASH' ){
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| 209 | $elem = "{'${class}::$name'}";
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| 210 | }
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| 211 | if( defined $arrays{$name} ){
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| 212 | $out .= " my \$i;\n";
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| 213 | $out .= " \@_ ? (\$i = shift) : return \$r->$elem;\n";
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| 214 | $sel = "->[\$i]";
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| 215 | }
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| 216 | elsif( defined $hashes{$name} ){
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| 217 | $out .= " my \$i;\n";
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| 218 | $out .= " \@_ ? (\$i = shift) : return \$r->$elem;\n";
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| 219 | $sel = "->{\$i}";
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| 220 | }
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| 221 | elsif( defined $classes{$name} ){
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| 222 | if ( $CHECK_CLASS_MEMBERSHIP ) {
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| 223 | $out .= " croak '$name argument is wrong class' if \@_ && ! UNIVERSAL::isa(\$_[0], '$classes{$name}');\n";
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| 224 | }
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| 225 | }
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| 226 | $out .= " croak 'Too many args to $name' if \@_ > 1;\n";
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| 227 | $out .= " \@_ ? ($pre\$r->$elem$sel = shift$pst) : $pre\$r->$elem$sel$pst;\n";
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| 228 | $out .= " }\n";
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| 229 | }
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| 230 | }
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| 231 | $out .= "}\n1;\n";
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| 232 |
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| 233 | print $out if $print;
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| 234 | my $result = eval $out;
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| 235 | carp $@ if $@;
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| 236 | }
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| 237 |
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| 238 | sub _usage_error {
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| 239 | confess "struct usage error";
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| 240 | }
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| 241 |
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| 242 | sub _subclass_error {
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| 243 | croak 'struct class cannot be a subclass (@ISA not allowed)';
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| 244 | }
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| 245 |
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| 246 | 1; # for require
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| 247 |
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| 248 |
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| 249 | __END__
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| 250 |
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| 251 | =head1 NAME
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| 252 |
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| 253 | Automake::Struct - declare struct-like datatypes as Perl classes
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| 254 |
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| 255 | =head1 SYNOPSIS
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| 256 |
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| 257 | use Automake::Struct;
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| 258 | # declare struct, based on array:
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| 259 | struct( CLASS_NAME => [ ELEMENT_NAME => ELEMENT_TYPE, ... ]);
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| 260 | # declare struct, based on hash:
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| 261 | struct( CLASS_NAME => { ELEMENT_NAME => ELEMENT_TYPE, ... });
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| 262 |
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| 263 | package CLASS_NAME;
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| 264 | use Automake::Struct;
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| 265 | # declare struct, based on array, implicit class name:
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| 266 | struct( ELEMENT_NAME => ELEMENT_TYPE, ... );
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| 267 |
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| 268 |
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| 269 | package Myobj;
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| 270 | use Automake::Struct;
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| 271 | # declare struct with four types of elements:
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| 272 | struct( s => '$', a => '@', h => '%', c => 'My_Other_Class' );
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| 273 |
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| 274 | $obj = new Myobj; # constructor
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| 275 |
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| 276 | # scalar type accessor:
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| 277 | $element_value = $obj->s; # element value
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| 278 | $obj->s('new value'); # assign to element
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| 279 |
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| 280 | # array type accessor:
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| 281 | $ary_ref = $obj->a; # reference to whole array
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| 282 | $ary_element_value = $obj->a(2); # array element value
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| 283 | $obj->a(2, 'new value'); # assign to array element
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| 284 |
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| 285 | # hash type accessor:
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| 286 | $hash_ref = $obj->h; # reference to whole hash
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| 287 | $hash_element_value = $obj->h('x'); # hash element value
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| 288 | $obj->h('x', 'new value'); # assign to hash element
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| 289 |
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| 290 | # class type accessor:
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| 291 | $element_value = $obj->c; # object reference
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| 292 | $obj->c->method(...); # call method of object
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| 293 | $obj->c(new My_Other_Class); # assign a new object
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| 294 |
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| 295 |
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| 296 | =head1 DESCRIPTION
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| 297 |
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| 298 | C<Automake::Struct> exports a single function, C<struct>.
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| 299 | Given a list of element names and types, and optionally
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| 300 | a class name, C<struct> creates a Perl 5 class that implements
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| 301 | a "struct-like" data structure.
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| 302 |
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| 303 | The new class is given a constructor method, C<new>, for creating
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| 304 | struct objects.
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| 305 |
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| 306 | Each element in the struct data has an accessor method, which is
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| 307 | used to assign to the element and to fetch its value. The
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| 308 | default accessor can be overridden by declaring a C<sub> of the
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| 309 | same name in the package. (See Example 2.)
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| 310 |
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| 311 | Each element's type can be scalar, array, hash, or class.
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| 312 |
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| 313 |
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| 314 | =head2 The C<struct()> function
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| 315 |
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| 316 | The C<struct> function has three forms of parameter-list.
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| 317 |
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| 318 | struct( CLASS_NAME => [ ELEMENT_LIST ]);
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| 319 | struct( CLASS_NAME => { ELEMENT_LIST });
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| 320 | struct( ELEMENT_LIST );
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| 321 |
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| 322 | The first and second forms explicitly identify the name of the
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| 323 | class being created. The third form assumes the current package
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| 324 | name as the class name.
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| 325 |
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| 326 | An object of a class created by the first and third forms is
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| 327 | based on an array, whereas an object of a class created by the
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| 328 | second form is based on a hash. The array-based forms will be
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| 329 | somewhat faster and smaller; the hash-based forms are more
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| 330 | flexible.
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| 331 |
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| 332 | The class created by C<struct> must not be a subclass of another
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| 333 | class other than C<UNIVERSAL>.
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| 334 |
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| 335 | It can, however, be used as a superclass for other classes. To facilitate
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| 336 | this, the generated constructor method uses a two-argument blessing.
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| 337 | Furthermore, if the class is hash-based, the key of each element is
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| 338 | prefixed with the class name (see I<Perl Cookbook>, Recipe 13.12).
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| 339 |
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| 340 | A function named C<new> must not be explicitly defined in a class
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| 341 | created by C<struct>.
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| 342 |
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| 343 | The I<ELEMENT_LIST> has the form
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| 344 |
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| 345 | NAME => TYPE, ...
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| 346 |
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| 347 | Each name-type pair declares one element of the struct. Each
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| 348 | element name will be defined as an accessor method unless a
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| 349 | method by that name is explicitly defined; in the latter case, a
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| 350 | warning is issued if the warning flag (B<-w>) is set.
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| 351 |
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| 352 |
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| 353 | =head2 Element Types and Accessor Methods
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| 354 |
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| 355 | The four element types -- scalar, array, hash, and class -- are
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| 356 | represented by strings -- C<'$'>, C<'@'>, C<'%'>, and a class name --
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| 357 | optionally preceded by a C<'*'>.
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| 358 |
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| 359 | The accessor method provided by C<struct> for an element depends
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| 360 | on the declared type of the element.
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| 361 |
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| 362 | =over
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| 363 |
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| 364 | =item Scalar (C<'$'> or C<'*$'>)
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| 365 |
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| 366 | The element is a scalar, and by default is initialized to C<undef>
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| 367 | (but see L<Initializing with new>).
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| 368 |
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| 369 | The accessor's argument, if any, is assigned to the element.
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| 370 |
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| 371 | If the element type is C<'$'>, the value of the element (after
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| 372 | assignment) is returned. If the element type is C<'*$'>, a reference
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| 373 | to the element is returned.
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| 374 |
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| 375 | =item Array (C<'@'> or C<'*@'>)
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| 376 |
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| 377 | The element is an array, initialized by default to C<()>.
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| 378 |
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| 379 | With no argument, the accessor returns a reference to the
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| 380 | element's whole array (whether or not the element was
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| 381 | specified as C<'@'> or C<'*@'>).
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| 382 |
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| 383 | With one or two arguments, the first argument is an index
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| 384 | specifying one element of the array; the second argument, if
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| 385 | present, is assigned to the array element. If the element type
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| 386 | is C<'@'>, the accessor returns the array element value. If the
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| 387 | element type is C<'*@'>, a reference to the array element is
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| 388 | returned.
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| 389 |
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| 390 | =item Hash (C<'%'> or C<'*%'>)
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| 391 |
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| 392 | The element is a hash, initialized by default to C<()>.
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| 393 |
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| 394 | With no argument, the accessor returns a reference to the
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| 395 | element's whole hash (whether or not the element was
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| 396 | specified as C<'%'> or C<'*%'>).
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| 397 |
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| 398 | With one or two arguments, the first argument is a key specifying
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| 399 | one element of the hash; the second argument, if present, is
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| 400 | assigned to the hash element. If the element type is C<'%'>, the
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| 401 | accessor returns the hash element value. If the element type is
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| 402 | C<'*%'>, a reference to the hash element is returned.
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| 403 |
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| 404 | =item Class (C<'Class_Name'> or C<'*Class_Name'>)
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| 405 |
|
|---|
| 406 | The element's value must be a reference blessed to the named
|
|---|
| 407 | class or to one of its subclasses. The element is initialized to
|
|---|
| 408 | the result of calling the C<new> constructor of the named class.
|
|---|
| 409 |
|
|---|
| 410 | The accessor's argument, if any, is assigned to the element. The
|
|---|
| 411 | accessor will C<croak> if this is not an appropriate object
|
|---|
| 412 | reference.
|
|---|
| 413 |
|
|---|
| 414 | If the element type does not start with a C<'*'>, the accessor
|
|---|
| 415 | returns the element value (after assignment). If the element type
|
|---|
| 416 | starts with a C<'*'>, a reference to the element itself is returned.
|
|---|
| 417 |
|
|---|
| 418 | =back
|
|---|
| 419 |
|
|---|
| 420 | =head2 Initializing with C<new>
|
|---|
| 421 |
|
|---|
| 422 | C<struct> always creates a constructor called C<new>. That constructor
|
|---|
| 423 | may take a list of initializers for the various elements of the new
|
|---|
| 424 | struct.
|
|---|
| 425 |
|
|---|
| 426 | Each initializer is a pair of values: I<element name>C< =E<gt> >I<value>.
|
|---|
| 427 | The initializer value for a scalar element is just a scalar value. The
|
|---|
| 428 | initializer for an array element is an array reference. The initializer
|
|---|
| 429 | for a hash is a hash reference.
|
|---|
| 430 |
|
|---|
| 431 | The initializer for a class element is also a hash reference, and the
|
|---|
| 432 | contents of that hash are passed to the element's own constructor.
|
|---|
| 433 |
|
|---|
| 434 | See Example 3 below for an example of initialization.
|
|---|
| 435 |
|
|---|
| 436 |
|
|---|
| 437 | =head1 EXAMPLES
|
|---|
| 438 |
|
|---|
| 439 | =over
|
|---|
| 440 |
|
|---|
| 441 | =item Example 1
|
|---|
| 442 |
|
|---|
| 443 | Giving a struct element a class type that is also a struct is how
|
|---|
| 444 | structs are nested. Here, C<timeval> represents a time (seconds and
|
|---|
| 445 | microseconds), and C<rusage> has two elements, each of which is of
|
|---|
| 446 | type C<timeval>.
|
|---|
| 447 |
|
|---|
| 448 | use Automake::Struct;
|
|---|
| 449 |
|
|---|
| 450 | struct( rusage => {
|
|---|
| 451 | ru_utime => timeval, # seconds
|
|---|
| 452 | ru_stime => timeval, # microseconds
|
|---|
| 453 | });
|
|---|
| 454 |
|
|---|
| 455 | struct( timeval => [
|
|---|
| 456 | tv_secs => '$',
|
|---|
| 457 | tv_usecs => '$',
|
|---|
| 458 | ]);
|
|---|
| 459 |
|
|---|
| 460 | # create an object:
|
|---|
| 461 | my $t = new rusage;
|
|---|
| 462 |
|
|---|
| 463 | # $t->ru_utime and $t->ru_stime are objects of type timeval.
|
|---|
| 464 | # set $t->ru_utime to 100.0 sec and $t->ru_stime to 5.0 sec.
|
|---|
| 465 | $t->ru_utime->tv_secs(100);
|
|---|
| 466 | $t->ru_utime->tv_usecs(0);
|
|---|
| 467 | $t->ru_stime->tv_secs(5);
|
|---|
| 468 | $t->ru_stime->tv_usecs(0);
|
|---|
| 469 |
|
|---|
| 470 |
|
|---|
| 471 | =item Example 2
|
|---|
| 472 |
|
|---|
| 473 | An accessor function can be redefined in order to provide
|
|---|
| 474 | additional checking of values, etc. Here, we want the C<count>
|
|---|
| 475 | element always to be nonnegative, so we redefine the C<count>
|
|---|
| 476 | accessor accordingly.
|
|---|
| 477 |
|
|---|
| 478 | package MyObj;
|
|---|
| 479 | use Automake::Struct;
|
|---|
| 480 |
|
|---|
| 481 | # declare the struct
|
|---|
| 482 | struct ( 'MyObj', { count => '$', stuff => '%' } );
|
|---|
| 483 |
|
|---|
| 484 | # override the default accessor method for 'count'
|
|---|
| 485 | sub count {
|
|---|
| 486 | my $self = shift;
|
|---|
| 487 | if ( @_ ) {
|
|---|
| 488 | die 'count must be nonnegative' if $_[0] < 0;
|
|---|
| 489 | $self->{'count'} = shift;
|
|---|
| 490 | warn "Too many args to count" if @_;
|
|---|
| 491 | }
|
|---|
| 492 | return $self->{'count'};
|
|---|
| 493 | }
|
|---|
| 494 |
|
|---|
| 495 | package main;
|
|---|
| 496 | $x = new MyObj;
|
|---|
| 497 | print "\$x->count(5) = ", $x->count(5), "\n";
|
|---|
| 498 | # prints '$x->count(5) = 5'
|
|---|
| 499 |
|
|---|
| 500 | print "\$x->count = ", $x->count, "\n";
|
|---|
| 501 | # prints '$x->count = 5'
|
|---|
| 502 |
|
|---|
| 503 | print "\$x->count(-5) = ", $x->count(-5), "\n";
|
|---|
| 504 | # dies due to negative argument!
|
|---|
| 505 |
|
|---|
| 506 | =item Example 3
|
|---|
| 507 |
|
|---|
| 508 | The constructor of a generated class can be passed a list
|
|---|
| 509 | of I<element>=>I<value> pairs, with which to initialize the struct.
|
|---|
| 510 | If no initializer is specified for a particular element, its default
|
|---|
| 511 | initialization is performed instead. Initializers for non-existent
|
|---|
| 512 | elements are silently ignored.
|
|---|
| 513 |
|
|---|
| 514 | Note that the initializer for a nested struct is specified
|
|---|
| 515 | as an anonymous hash of initializers, which is passed on to the nested
|
|---|
| 516 | struct's constructor.
|
|---|
| 517 |
|
|---|
| 518 |
|
|---|
| 519 | use Automake::Struct;
|
|---|
| 520 |
|
|---|
| 521 | struct Breed =>
|
|---|
| 522 | {
|
|---|
| 523 | name => '$',
|
|---|
| 524 | cross => '$',
|
|---|
| 525 | };
|
|---|
| 526 |
|
|---|
| 527 | struct Cat =>
|
|---|
| 528 | [
|
|---|
| 529 | name => '$',
|
|---|
| 530 | kittens => '@',
|
|---|
| 531 | markings => '%',
|
|---|
| 532 | breed => 'Breed',
|
|---|
| 533 | ];
|
|---|
| 534 |
|
|---|
| 535 |
|
|---|
| 536 | my $cat = Cat->new( name => 'Socks',
|
|---|
| 537 | kittens => ['Monica', 'Kenneth'],
|
|---|
| 538 | markings => { socks=>1, blaze=>"white" },
|
|---|
| 539 | breed => { name=>'short-hair', cross=>1 },
|
|---|
| 540 | );
|
|---|
| 541 |
|
|---|
| 542 | print "Once a cat called ", $cat->name, "\n";
|
|---|
| 543 | print "(which was a ", $cat->breed->name, ")\n";
|
|---|
| 544 | print "had two kittens: ", join(' and ', @{$cat->kittens}), "\n";
|
|---|
| 545 |
|
|---|
| 546 | =back
|
|---|
| 547 |
|
|---|
| 548 | =head1 Author and Modification History
|
|---|
| 549 |
|
|---|
| 550 | Modified by Akim Demaille, 2001-08-03
|
|---|
| 551 |
|
|---|
| 552 | Rename as Automake::Struct to avoid name clashes with
|
|---|
| 553 | Class::Struct.
|
|---|
| 554 |
|
|---|
| 555 | Make it compatible with Perl 5.5.
|
|---|
| 556 |
|
|---|
| 557 | Modified by Damian Conway, 1999-03-05, v0.58.
|
|---|
| 558 |
|
|---|
| 559 | Added handling of hash-like arg list to class ctor.
|
|---|
| 560 |
|
|---|
| 561 | Changed to two-argument blessing in ctor to support
|
|---|
| 562 | derivation from created classes.
|
|---|
| 563 |
|
|---|
| 564 | Added classname prefixes to keys in hash-based classes
|
|---|
| 565 | (refer to "Perl Cookbook", Recipe 13.12 for rationale).
|
|---|
| 566 |
|
|---|
| 567 | Corrected behavior of accessors for '*@' and '*%' struct
|
|---|
| 568 | elements. Package now implements documented behavior when
|
|---|
| 569 | returning a reference to an entire hash or array element.
|
|---|
| 570 | Previously these were returned as a reference to a reference
|
|---|
| 571 | to the element.
|
|---|
| 572 |
|
|---|
| 573 |
|
|---|
| 574 | Renamed to C<Class::Struct> and modified by Jim Miner, 1997-04-02.
|
|---|
| 575 |
|
|---|
| 576 | members() function removed.
|
|---|
| 577 | Documentation corrected and extended.
|
|---|
| 578 | Use of struct() in a subclass prohibited.
|
|---|
| 579 | User definition of accessor allowed.
|
|---|
| 580 | Treatment of '*' in element types corrected.
|
|---|
| 581 | Treatment of classes as element types corrected.
|
|---|
| 582 | Class name to struct() made optional.
|
|---|
| 583 | Diagnostic checks added.
|
|---|
| 584 |
|
|---|
| 585 |
|
|---|
| 586 | Originally C<Class::Template> by Dean Roehrich.
|
|---|
| 587 |
|
|---|
| 588 | # Template.pm --- struct/member template builder
|
|---|
| 589 | # 12mar95
|
|---|
| 590 | # Dean Roehrich
|
|---|
| 591 | #
|
|---|
| 592 | # changes/bugs fixed since 28nov94 version:
|
|---|
| 593 | # - podified
|
|---|
| 594 | # changes/bugs fixed since 21nov94 version:
|
|---|
| 595 | # - Fixed examples.
|
|---|
| 596 | # changes/bugs fixed since 02sep94 version:
|
|---|
| 597 | # - Moved to Class::Template.
|
|---|
| 598 | # changes/bugs fixed since 20feb94 version:
|
|---|
| 599 | # - Updated to be a more proper module.
|
|---|
| 600 | # - Added "use strict".
|
|---|
| 601 | # - Bug in build_methods, was using @var when @$var needed.
|
|---|
| 602 | # - Now using my() rather than local().
|
|---|
| 603 | #
|
|---|
| 604 | # Uses perl5 classes to create nested data types.
|
|---|
| 605 | # This is offered as one implementation of Tom Christiansen's "structs.pl"
|
|---|
| 606 | # idea.
|
|---|
| 607 |
|
|---|
| 608 | =cut
|
|---|
| 609 |
|
|---|
| 610 | ### Setup "GNU" style for perl-mode and cperl-mode.
|
|---|
| 611 | ## Local Variables:
|
|---|
| 612 | ## perl-indent-level: 2
|
|---|
| 613 | ## perl-continued-statement-offset: 2
|
|---|
| 614 | ## perl-continued-brace-offset: 0
|
|---|
| 615 | ## perl-brace-offset: 0
|
|---|
| 616 | ## perl-brace-imaginary-offset: 0
|
|---|
| 617 | ## perl-label-offset: -2
|
|---|
| 618 | ## cperl-indent-level: 2
|
|---|
| 619 | ## cperl-brace-offset: 0
|
|---|
| 620 | ## cperl-continued-brace-offset: 0
|
|---|
| 621 | ## cperl-label-offset: -2
|
|---|
| 622 | ## cperl-extra-newline-before-brace: t
|
|---|
| 623 | ## cperl-merge-trailing-else: nil
|
|---|
| 624 | ## cperl-continued-statement-offset: 2
|
|---|
| 625 | ## End:
|
|---|
