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