[DOC PATCH] Carp.pm pod typo
[p5sagit/p5-mst-13.2.git] / lib / Exporter / Heavy.pm
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b75c8c73 1package Exporter::Heavy;
2
3use strict;
4no strict 'refs';
5
6# On one line so MakeMaker will see it.
7require Exporter; our $VERSION = $Exporter::VERSION;
8
9our $Verbose;
4af1b167 10
ca24dfc6 11=head1 NAME
12
13Exporter::Heavy - Exporter guts
14
15=head1 SYNOPIS
16
17(internal use only)
18
19=head1 DESCRIPTION
20
21No user-serviceable parts inside.
3cb6de81 22
ca24dfc6 23=cut
4ac9195f 24
4af1b167 25#
26# We go to a lot of trouble not to 'require Carp' at file scope,
27# because Carp requires Exporter, and something has to give.
28#
29
30sub heavy_export {
31
32 # First make import warnings look like they're coming from the "use".
33 local $SIG{__WARN__} = sub {
34 my $text = shift;
35 if ($text =~ s/ at \S*Exporter\S*.pm line \d+.*\n//) {
36 require Carp;
37 local $Carp::CarpLevel = 1; # ignore package calling us too.
38 Carp::carp($text);
39 }
40 else {
41 warn $text;
42 }
43 };
44 local $SIG{__DIE__} = sub {
45 require Carp;
46 local $Carp::CarpLevel = 1; # ignore package calling us too.
47 Carp::croak("$_[0]Illegal null symbol in \@${1}::EXPORT")
48 if $_[0] =~ /^Unable to create sub named "(.*?)::"/;
49 };
50
51 my($pkg, $callpkg, @imports) = @_;
52 my($type, $sym, $oops);
b75c8c73 53 my($exports, $export_cache) = (\@{"${pkg}::EXPORT"},
54 \%{"${pkg}::EXPORT"});
4af1b167 55
56 if (@imports) {
b75c8c73 57 if (!%$export_cache) {
58 s/^&// foreach @$exports;
59 @{$export_cache}{@$exports} = (1) x @$exports;
4af1b167 60 my $ok = \@{"${pkg}::EXPORT_OK"};
61 if (@$ok) {
b75c8c73 62 s/^&// foreach @$ok;
63 @{$export_cache}{@$ok} = (1) x @$ok;
4af1b167 64 }
65 }
66
67 if ($imports[0] =~ m#^[/!:]#){
68 my $tagsref = \%{"${pkg}::EXPORT_TAGS"};
69 my $tagdata;
70 my %imports;
71 my($remove, $spec, @names, @allexports);
72 # negated first item implies starting with default set:
73 unshift @imports, ':DEFAULT' if $imports[0] =~ m/^!/;
74 foreach $spec (@imports){
75 $remove = $spec =~ s/^!//;
76
77 if ($spec =~ s/^://){
78 if ($spec eq 'DEFAULT'){
b75c8c73 79 @names = @$exports;
4af1b167 80 }
81 elsif ($tagdata = $tagsref->{$spec}) {
82 @names = @$tagdata;
83 }
84 else {
85 warn qq["$spec" is not defined in %${pkg}::EXPORT_TAGS];
86 ++$oops;
87 next;
88 }
89 }
90 elsif ($spec =~ m:^/(.*)/$:){
91 my $patn = $1;
b75c8c73 92 @allexports = keys %$export_cache unless @allexports; # only do keys once
4af1b167 93 @names = grep(/$patn/, @allexports); # not anchored by default
94 }
95 else {
96 @names = ($spec); # is a normal symbol name
97 }
98
99 warn "Import ".($remove ? "del":"add").": @names "
100 if $Verbose;
101
102 if ($remove) {
103 foreach $sym (@names) { delete $imports{$sym} }
104 }
105 else {
106 @imports{@names} = (1) x @names;
107 }
108 }
109 @imports = keys %imports;
110 }
111
112 foreach $sym (@imports) {
b75c8c73 113 if (!$export_cache->{$sym}) {
4af1b167 114 if ($sym =~ m/^\d/) {
115 $pkg->require_version($sym);
116 # If the version number was the only thing specified
117 # then we should act as if nothing was specified:
118 if (@imports == 1) {
b75c8c73 119 @imports = @$exports;
4af1b167 120 last;
121 }
122 # We need a way to emulate 'use Foo ()' but still
123 # allow an easy version check: "use Foo 1.23, ''";
124 if (@imports == 2 and !$imports[1]) {
125 @imports = ();
126 last;
127 }
b75c8c73 128 } elsif ($sym !~ s/^&// || !$export_cache->{$sym}) {
4af1b167 129 require Carp;
130 Carp::carp(qq["$sym" is not exported by the $pkg module]);
131 $oops++;
132 }
133 }
134 }
135 if ($oops) {
136 require Carp;
137 Carp::croak("Can't continue after import errors");
138 }
139 }
140 else {
b75c8c73 141 @imports = @$exports;
4af1b167 142 }
143
b75c8c73 144 my($fail, $fail_cache) = (\@{"${pkg}::EXPORT_FAIL"},
145 \%{"${pkg}::EXPORT_FAIL"});
146
147 if (@$fail) {
148 if (!%$fail_cache) {
4af1b167 149 # Build cache of symbols. Optimise the lookup by adding
150 # barewords twice... both with and without a leading &.
b75c8c73 151 # (Technique could be applied to $export_cache at cost of memory)
152 my @expanded = map { /^\w/ ? ($_, '&'.$_) : $_ } @$fail;
4af1b167 153 warn "${pkg}::EXPORT_FAIL cached: @expanded" if $Verbose;
b75c8c73 154 @{$fail_cache}{@expanded} = (1) x @expanded;
4af1b167 155 }
156 my @failed;
b75c8c73 157 foreach $sym (@imports) { push(@failed, $sym) if $fail_cache->{$sym} }
4af1b167 158 if (@failed) {
159 @failed = $pkg->export_fail(@failed);
160 foreach $sym (@failed) {
161 require Carp;
162 Carp::carp(qq["$sym" is not implemented by the $pkg module ],
163 "on this architecture");
164 }
165 if (@failed) {
166 require Carp;
167 Carp::croak("Can't continue after import errors");
168 }
169 }
170 }
171
172 warn "Importing into $callpkg from $pkg: ",
173 join(", ",sort @imports) if $Verbose;
174
175 foreach $sym (@imports) {
176 # shortcut for the common case of no type character
177 (*{"${callpkg}::$sym"} = \&{"${pkg}::$sym"}, next)
178 unless $sym =~ s/^(\W)//;
179 $type = $1;
180 *{"${callpkg}::$sym"} =
181 $type eq '&' ? \&{"${pkg}::$sym"} :
182 $type eq '$' ? \${"${pkg}::$sym"} :
183 $type eq '@' ? \@{"${pkg}::$sym"} :
184 $type eq '%' ? \%{"${pkg}::$sym"} :
185 $type eq '*' ? *{"${pkg}::$sym"} :
186 do { require Carp; Carp::croak("Can't export symbol: $type$sym") };
187 }
188}
189
190sub heavy_export_to_level
191{
192 my $pkg = shift;
193 my $level = shift;
31a63159 194 (undef) = shift; # XXX redundant arg
4af1b167 195 my $callpkg = caller($level);
196 $pkg->export($callpkg, @_);
197}
198
199# Utility functions
200
201sub _push_tags {
202 my($pkg, $var, $syms) = @_;
b75c8c73 203 my @nontag = ();
204 my $export_tags = \%{"${pkg}::EXPORT_TAGS"};
4af1b167 205 push(@{"${pkg}::$var"},
b75c8c73 206 map { $export_tags->{$_} ? @{$export_tags->{$_}}
207 : scalar(push(@nontag,$_),$_) }
208 (@$syms) ? @$syms : keys %$export_tags);
209 if (@nontag and $^W) {
4af1b167 210 # This may change to a die one day
211 require Carp;
b75c8c73 212 Carp::carp(join(", ", @nontag)." are not tags of $pkg");
4af1b167 213 }
214}
215
4af1b167 216
217sub require_version {
218 my($self, $wanted) = @_;
219 my $pkg = ref $self || $self;
220 my $version = ${"${pkg}::VERSION"};
94dd7035 221 if (!defined $version or $version < $wanted) {
222 $version = defined $version ? $version : "(undef)";
767440f4 223 # %INC contains slashes, but $pkg contains double-colons.
224 my $file = (map {s,::,/,g; $INC{$_}} "$pkg.pm")[0];
94dd7035 225 $file = defined $file ? " ($file)" : '';
4af1b167 226 require Carp;
227 Carp::croak("$pkg $wanted required--this is only version $version$file")
228 }
229 $version;
230}
231
2321;