| Filename | /home/micha/.plenv/versions/5.38.2/lib/perl5/5.38.2/Symbol.pm |
| Statements | Executed 57 statements in 619µs |
| Calls | P | F | Exclusive Time |
Inclusive Time |
Subroutine |
|---|---|---|---|---|---|
| 9 | 1 | 1 | 32µs | 32µs | Symbol::gensym |
| 1 | 1 | 1 | 8µs | 10µs | Symbol::BEGIN@3 |
| 1 | 1 | 1 | 8µs | 23µs | Symbol::BEGIN@4 |
| 1 | 1 | 1 | 6µs | 10µs | Symbol::BEGIN@137 |
| 1 | 1 | 1 | 6µs | 10µs | Symbol::BEGIN@156 |
| 1 | 1 | 1 | 5µs | 11µs | Symbol::BEGIN@103 |
| 1 | 1 | 1 | 5µs | 7µs | Symbol::BEGIN@167 |
| 0 | 0 | 0 | 0s | 0s | Symbol::delete_package |
| 0 | 0 | 0 | 0s | 0s | Symbol::geniosym |
| 0 | 0 | 0 | 0s | 0s | Symbol::qualify |
| 0 | 0 | 0 | 0s | 0s | Symbol::qualify_to_ref |
| 0 | 0 | 0 | 0s | 0s | Symbol::ungensym |
| Line | State ments |
Time on line |
Calls | Time in subs |
Code |
|---|---|---|---|---|---|
| 1 | package Symbol; | ||||
| 2 | |||||
| 3 | 2 | 16µs | 2 | 11µs | # spent 10µs (8+1) within Symbol::BEGIN@3 which was called:
# once (8µs+1µs) by IO::File::BEGIN@122 at line 3 # spent 10µs making 1 call to Symbol::BEGIN@3
# spent 1µs making 1 call to strict::import |
| 4 | 2 | 94µs | 2 | 39µs | # spent 23µs (8+15) within Symbol::BEGIN@4 which was called:
# once (8µs+15µs) by IO::File::BEGIN@122 at line 4 # spent 23µs making 1 call to Symbol::BEGIN@4
# spent 15µs making 1 call to warnings::import |
| 5 | |||||
| 6 | =head1 NAME | ||||
| 7 | |||||
| 8 | Symbol - manipulate Perl symbols and their names | ||||
| 9 | |||||
| 10 | =head1 SYNOPSIS | ||||
| 11 | |||||
| 12 | use Symbol; | ||||
| 13 | |||||
| 14 | $sym = gensym; | ||||
| 15 | open($sym, '<', "filename"); | ||||
| 16 | $_ = <$sym>; | ||||
| 17 | # etc. | ||||
| 18 | |||||
| 19 | ungensym $sym; # no effect | ||||
| 20 | |||||
| 21 | # replace *FOO{IO} handle but not $FOO, %FOO, etc. | ||||
| 22 | *FOO = geniosym; | ||||
| 23 | |||||
| 24 | print qualify("x"), "\n"; # "main::x" | ||||
| 25 | print qualify("x", "FOO"), "\n"; # "FOO::x" | ||||
| 26 | print qualify("BAR::x"), "\n"; # "BAR::x" | ||||
| 27 | print qualify("BAR::x", "FOO"), "\n"; # "BAR::x" | ||||
| 28 | print qualify("STDOUT", "FOO"), "\n"; # "main::STDOUT" (global) | ||||
| 29 | print qualify(\*x), "\n"; # returns \*x | ||||
| 30 | print qualify(\*x, "FOO"), "\n"; # returns \*x | ||||
| 31 | |||||
| 32 | use strict refs; | ||||
| 33 | print { qualify_to_ref $fh } "foo!\n"; | ||||
| 34 | $ref = qualify_to_ref $name, $pkg; | ||||
| 35 | |||||
| 36 | use Symbol qw(delete_package); | ||||
| 37 | delete_package('Foo::Bar'); | ||||
| 38 | print "deleted\n" unless exists $Foo::{'Bar::'}; | ||||
| 39 | |||||
| 40 | =head1 DESCRIPTION | ||||
| 41 | |||||
| 42 | C<Symbol::gensym> creates an anonymous glob and returns a reference | ||||
| 43 | to it. Such a glob reference can be used as a file or directory | ||||
| 44 | handle. | ||||
| 45 | |||||
| 46 | For backward compatibility with older implementations that didn't | ||||
| 47 | support anonymous globs, C<Symbol::ungensym> is also provided. | ||||
| 48 | But it doesn't do anything. | ||||
| 49 | |||||
| 50 | C<Symbol::geniosym> creates an anonymous IO handle. This can be | ||||
| 51 | assigned into an existing glob without affecting the non-IO portions | ||||
| 52 | of the glob. | ||||
| 53 | |||||
| 54 | C<Symbol::qualify> turns unqualified symbol names into qualified | ||||
| 55 | variable names (e.g. "myvar" -E<gt> "MyPackage::myvar"). If it is given a | ||||
| 56 | second parameter, C<qualify> uses it as the default package; | ||||
| 57 | otherwise, it uses the package of its caller. Regardless, global | ||||
| 58 | variable names (e.g. "STDOUT", "ENV", "SIG") are always qualified with | ||||
| 59 | "main::". | ||||
| 60 | |||||
| 61 | Qualification applies only to symbol names (strings). References are | ||||
| 62 | left unchanged under the assumption that they are glob references, | ||||
| 63 | which are qualified by their nature. | ||||
| 64 | |||||
| 65 | C<Symbol::qualify_to_ref> is just like C<Symbol::qualify> except that it | ||||
| 66 | returns a glob ref rather than a symbol name, so you can use the result | ||||
| 67 | even if C<use strict 'refs'> is in effect. | ||||
| 68 | |||||
| 69 | C<Symbol::delete_package> wipes out a whole package namespace. Note | ||||
| 70 | this routine is not exported by default--you may want to import it | ||||
| 71 | explicitly. | ||||
| 72 | |||||
| 73 | =head1 BUGS | ||||
| 74 | |||||
| 75 | C<Symbol::delete_package> is a bit too powerful. It undefines every symbol that | ||||
| 76 | lives in the specified package. Since perl, for performance reasons, does not | ||||
| 77 | perform a symbol table lookup each time a function is called or a global | ||||
| 78 | variable is accessed, some code that has already been loaded and that makes use | ||||
| 79 | of symbols in package C<Foo> may stop working after you delete C<Foo>, even if | ||||
| 80 | you reload the C<Foo> module afterwards. | ||||
| 81 | |||||
| 82 | =cut | ||||
| 83 | |||||
| 84 | 1 | 300ns | require Exporter; | ||
| 85 | 1 | 5µs | our @ISA = qw(Exporter); | ||
| 86 | 1 | 500ns | our @EXPORT = qw(gensym ungensym qualify qualify_to_ref); | ||
| 87 | 1 | 200ns | our @EXPORT_OK = qw(delete_package geniosym); | ||
| 88 | |||||
| 89 | 1 | 200ns | our $VERSION = '1.09'; | ||
| 90 | |||||
| 91 | 1 | 200ns | my $genpkg = "Symbol::"; | ||
| 92 | 1 | 100ns | my $genseq = 0; | ||
| 93 | |||||
| 94 | 1 | 3µs | my %global = map {$_ => 1} qw(ARGV ARGVOUT ENV INC SIG STDERR STDIN STDOUT); | ||
| 95 | |||||
| 96 | # | ||||
| 97 | # Note that we never _copy_ the glob; we just make a ref to it. | ||||
| 98 | # If we did copy it, then SVf_FAKE would be set on the copy, and | ||||
| 99 | # glob-specific behaviors (e.g. C<*$ref = \&func>) wouldn't work. | ||||
| 100 | # | ||||
| 101 | # spent 32µs within Symbol::gensym which was called 9 times, avg 4µs/call:
# 9 times (32µs+0s) by IO::Handle::new at line 333 of IO/Handle.pm, avg 4µs/call | ||||
| 102 | 9 | 5µs | my $name = "GEN" . $genseq++; | ||
| 103 | 2 | 199µs | 2 | 17µs | # spent 11µs (5+6) within Symbol::BEGIN@103 which was called:
# once (5µs+6µs) by IO::File::BEGIN@122 at line 103 # spent 11µs making 1 call to Symbol::BEGIN@103
# spent 6µs making 1 call to strict::unimport |
| 104 | 9 | 16µs | my $ref = \*{$genpkg . $name}; | ||
| 105 | 9 | 5µs | delete $$genpkg{$name}; | ||
| 106 | 9 | 11µs | $ref; | ||
| 107 | } | ||||
| 108 | |||||
| 109 | sub geniosym () { | ||||
| 110 | my $sym = gensym(); | ||||
| 111 | # force the IO slot to be filled | ||||
| 112 | select(select $sym); | ||||
| 113 | *$sym{IO}; | ||||
| 114 | } | ||||
| 115 | |||||
| 116 | sub ungensym ($) {} | ||||
| 117 | |||||
| 118 | sub qualify ($;$) { | ||||
| 119 | my ($name) = @_; | ||||
| 120 | if (!ref($name) && index($name, '::') == -1 && index($name, "'") == -1) { | ||||
| 121 | my $pkg; | ||||
| 122 | # Global names: special character, "^xyz", or other. | ||||
| 123 | if ($name =~ /^(([^a-z])|(\^[a-z_]+))\z/i || $global{$name}) { | ||||
| 124 | # RGS 2001-11-05 : translate leading ^X to control-char | ||||
| 125 | $name =~ s/^\^([a-z_])/'qq(\c'.$1.')'/eei; | ||||
| 126 | $pkg = "main"; | ||||
| 127 | } | ||||
| 128 | else { | ||||
| 129 | $pkg = (@_ > 1) ? $_[1] : caller; | ||||
| 130 | } | ||||
| 131 | $name = $pkg . "::" . $name; | ||||
| 132 | } | ||||
| 133 | $name; | ||||
| 134 | } | ||||
| 135 | |||||
| 136 | sub qualify_to_ref ($;$) { | ||||
| 137 | 2 | 160µs | 2 | 14µs | # spent 10µs (6+4) within Symbol::BEGIN@137 which was called:
# once (6µs+4µs) by IO::File::BEGIN@122 at line 137 # spent 10µs making 1 call to Symbol::BEGIN@137
# spent 4µs making 1 call to strict::unimport |
| 138 | return \*{ qualify $_[0], @_ > 1 ? $_[1] : caller }; | ||||
| 139 | } | ||||
| 140 | |||||
| 141 | # | ||||
| 142 | # of Safe.pm lineage | ||||
| 143 | # | ||||
| 144 | sub delete_package ($) { | ||||
| 145 | my $pkg = shift; | ||||
| 146 | |||||
| 147 | # expand to full symbol table name if needed | ||||
| 148 | |||||
| 149 | unless ($pkg =~ /^main::.*::$/) { | ||||
| 150 | $pkg = "main$pkg" if $pkg =~ /^::/; | ||||
| 151 | $pkg = "main::$pkg" unless $pkg =~ /^main::/; | ||||
| 152 | $pkg .= '::' unless $pkg =~ /::$/; | ||||
| 153 | } | ||||
| 154 | |||||
| 155 | my($stem, $leaf) = $pkg =~ m/(.*::)(\w+::)$/; | ||||
| 156 | 2 | 50µs | 2 | 14µs | # spent 10µs (6+4) within Symbol::BEGIN@156 which was called:
# once (6µs+4µs) by IO::File::BEGIN@122 at line 156 # spent 10µs making 1 call to Symbol::BEGIN@156
# spent 4µs making 1 call to strict::unimport |
| 157 | my $stem_symtab = *{$stem}{HASH}; | ||||
| 158 | return unless defined $stem_symtab and exists $stem_symtab->{$leaf}; | ||||
| 159 | |||||
| 160 | |||||
| 161 | # free all the symbols in the package | ||||
| 162 | |||||
| 163 | my $leaf_symtab = *{$stem_symtab->{$leaf}}{HASH}; | ||||
| 164 | foreach my $name (keys %$leaf_symtab) { | ||||
| 165 | undef *{$pkg . $name}; | ||||
| 166 | } | ||||
| 167 | 2 | 50µs | 2 | 10µs | # spent 7µs (5+3) within Symbol::BEGIN@167 which was called:
# once (5µs+3µs) by IO::File::BEGIN@122 at line 167 # spent 7µs making 1 call to Symbol::BEGIN@167
# spent 3µs making 1 call to strict::import |
| 168 | |||||
| 169 | # delete the symbol table | ||||
| 170 | |||||
| 171 | %$leaf_symtab = (); | ||||
| 172 | delete $stem_symtab->{$leaf}; | ||||
| 173 | } | ||||
| 174 | |||||
| 175 | 1 | 4µs | 1; |