| File | /opt/wise/lib/perl5/5.10.0/Symbol.pm | Statements Executed | 14 | Total Time | 0.00064 seconds |
| Calls | P | F | Exclusive Time |
Inclusive Time |
Subroutine | |
|---|---|---|---|---|---|---|
| 1 | 1 | 1 | 1.8e-5 | 1.8e-5 | Symbol:: | gensym |
| 0 | 0 | 0 | 0 | 0 | Symbol:: | BEGIN |
| 0 | 0 | 0 | 0 | 0 | Symbol:: | delete_package |
| 0 | 0 | 0 | 0 | 0 | Symbol:: | geniosym |
| 0 | 0 | 0 | 0 | 0 | Symbol:: | qualify |
| 0 | 0 | 0 | 0 | 0 | Symbol:: | qualify_to_ref |
| 0 | 0 | 0 | 0 | 0 | Symbol:: | ungensym |
| Line | Stmts. | Exclusive Time | Avg. | Code |
|---|---|---|---|---|
| 1 | package Symbol; | |||
| 2 | ||||
| 3 | =head1 NAME | |||
| 4 | ||||
| 5 | Symbol - manipulate Perl symbols and their names | |||
| 6 | ||||
| 7 | =head1 SYNOPSIS | |||
| 8 | ||||
| 9 | use Symbol; | |||
| 10 | ||||
| 11 | $sym = gensym; | |||
| 12 | open($sym, "filename"); | |||
| 13 | $_ = <$sym>; | |||
| 14 | # etc. | |||
| 15 | ||||
| 16 | ungensym $sym; # no effect | |||
| 17 | ||||
| 18 | # replace *FOO{IO} handle but not $FOO, %FOO, etc. | |||
| 19 | *FOO = geniosym; | |||
| 20 | ||||
| 21 | print qualify("x"), "\n"; # "Test::x" | |||
| 22 | print qualify("x", "FOO"), "\n" # "FOO::x" | |||
| 23 | print qualify("BAR::x"), "\n"; # "BAR::x" | |||
| 24 | print qualify("BAR::x", "FOO"), "\n"; # "BAR::x" | |||
| 25 | print qualify("STDOUT", "FOO"), "\n"; # "main::STDOUT" (global) | |||
| 26 | print qualify(\*x), "\n"; # returns \*x | |||
| 27 | print qualify(\*x, "FOO"), "\n"; # returns \*x | |||
| 28 | ||||
| 29 | use strict refs; | |||
| 30 | print { qualify_to_ref $fh } "foo!\n"; | |||
| 31 | $ref = qualify_to_ref $name, $pkg; | |||
| 32 | ||||
| 33 | use Symbol qw(delete_package); | |||
| 34 | delete_package('Foo::Bar'); | |||
| 35 | print "deleted\n" unless exists $Foo::{'Bar::'}; | |||
| 36 | ||||
| 37 | =head1 DESCRIPTION | |||
| 38 | ||||
| 39 | C<Symbol::gensym> creates an anonymous glob and returns a reference | |||
| 40 | to it. Such a glob reference can be used as a file or directory | |||
| 41 | handle. | |||
| 42 | ||||
| 43 | For backward compatibility with older implementations that didn't | |||
| 44 | support anonymous globs, C<Symbol::ungensym> is also provided. | |||
| 45 | But it doesn't do anything. | |||
| 46 | ||||
| 47 | C<Symbol::geniosym> creates an anonymous IO handle. This can be | |||
| 48 | assigned into an existing glob without affecting the non-IO portions | |||
| 49 | of the glob. | |||
| 50 | ||||
| 51 | C<Symbol::qualify> turns unqualified symbol names into qualified | |||
| 52 | variable names (e.g. "myvar" -E<gt> "MyPackage::myvar"). If it is given a | |||
| 53 | second parameter, C<qualify> uses it as the default package; | |||
| 54 | otherwise, it uses the package of its caller. Regardless, global | |||
| 55 | variable names (e.g. "STDOUT", "ENV", "SIG") are always qualified with | |||
| 56 | "main::". | |||
| 57 | ||||
| 58 | Qualification applies only to symbol names (strings). References are | |||
| 59 | left unchanged under the assumption that they are glob references, | |||
| 60 | which are qualified by their nature. | |||
| 61 | ||||
| 62 | C<Symbol::qualify_to_ref> is just like C<Symbol::qualify> except that it | |||
| 63 | returns a glob ref rather than a symbol name, so you can use the result | |||
| 64 | even if C<use strict 'refs'> is in effect. | |||
| 65 | ||||
| 66 | C<Symbol::delete_package> wipes out a whole package namespace. Note | |||
| 67 | this routine is not exported by default--you may want to import it | |||
| 68 | explicitly. | |||
| 69 | ||||
| 70 | =head1 BUGS | |||
| 71 | ||||
| 72 | C<Symbol::delete_package> is a bit too powerful. It undefines every symbol that | |||
| 73 | lives in the specified package. Since perl, for performance reasons, does not | |||
| 74 | perform a symbol table lookup each time a function is called or a global | |||
| 75 | variable is accessed, some code that has already been loaded and that makes use | |||
| 76 | of symbols in package C<Foo> may stop working after you delete C<Foo>, even if | |||
| 77 | you reload the C<Foo> module afterwards. | |||
| 78 | ||||
| 79 | =cut | |||
| 80 | ||||
| 81 | 1 | 0.00059 | 0.00059 | BEGIN { require 5.005; } |
| 82 | ||||
| 83 | 1 | 1.0e-6 | 1.0e-6 | require Exporter; |
| 84 | 1 | 6.0e-6 | 6.0e-6 | @ISA = qw(Exporter); |
| 85 | 1 | 2.0e-6 | 2.0e-6 | @EXPORT = qw(gensym ungensym qualify qualify_to_ref); |
| 86 | 1 | 2.0e-6 | 2.0e-6 | @EXPORT_OK = qw(delete_package geniosym); |
| 87 | ||||
| 88 | 1 | 3.0e-6 | 3.0e-6 | $VERSION = '1.06'; |
| 89 | ||||
| 90 | 1 | 1.0e-6 | 1.0e-6 | my $genpkg = "Symbol::"; |
| 91 | 1 | 0 | 0 | my $genseq = 0; |
| 92 | ||||
| 93 | 1 | 1.4e-5 | 1.4e-5 | my %global = map {$_ => 1} qw(ARGV ARGVOUT ENV INC SIG STDERR STDIN STDOUT); |
| 94 | ||||
| 95 | # | |||
| 96 | # Note that we never _copy_ the glob; we just make a ref to it. | |||
| 97 | # If we did copy it, then SVf_FAKE would be set on the copy, and | |||
| 98 | # glob-specific behaviors (e.g. C<*$ref = \&func>) wouldn't work. | |||
| 99 | # | |||
| 100 | # spent 18µs within Symbol::gensym which was called
# once (18µs+0) by File::Slurp::read_file at line 135 of /wise/base/static/lib/perl5/site_perl/5.10.0/File/Slurp.pm | |||
| 101 | 4 | 1.2e-5 | 3.0e-6 | my $name = "GEN" . $genseq++; |
| 102 | my $ref = \*{$genpkg . $name}; | |||
| 103 | delete $$genpkg{$name}; | |||
| 104 | $ref; | |||
| 105 | } | |||
| 106 | ||||
| 107 | sub geniosym () { | |||
| 108 | my $sym = gensym(); | |||
| 109 | # force the IO slot to be filled | |||
| 110 | select(select $sym); | |||
| 111 | *$sym{IO}; | |||
| 112 | } | |||
| 113 | ||||
| 114 | sub ungensym ($) {} | |||
| 115 | ||||
| 116 | sub qualify ($;$) { | |||
| 117 | my ($name) = @_; | |||
| 118 | if (!ref($name) && index($name, '::') == -1 && index($name, "'") == -1) { | |||
| 119 | my $pkg; | |||
| 120 | # Global names: special character, "^xyz", or other. | |||
| 121 | if ($name =~ /^(([^a-z])|(\^[a-z_]+))\z/i || $global{$name}) { | |||
| 122 | # RGS 2001-11-05 : translate leading ^X to control-char | |||
| 123 | $name =~ s/^\^([a-z_])/'qq(\c'.$1.')'/eei; | |||
| 124 | $pkg = "main"; | |||
| 125 | } | |||
| 126 | else { | |||
| 127 | $pkg = (@_ > 1) ? $_[1] : caller; | |||
| 128 | } | |||
| 129 | $name = $pkg . "::" . $name; | |||
| 130 | } | |||
| 131 | $name; | |||
| 132 | } | |||
| 133 | ||||
| 134 | sub qualify_to_ref ($;$) { | |||
| 135 | return \*{ qualify $_[0], @_ > 1 ? $_[1] : caller }; | |||
| 136 | } | |||
| 137 | ||||
| 138 | # | |||
| 139 | # of Safe.pm lineage | |||
| 140 | # | |||
| 141 | sub delete_package ($) { | |||
| 142 | my $pkg = shift; | |||
| 143 | ||||
| 144 | # expand to full symbol table name if needed | |||
| 145 | ||||
| 146 | unless ($pkg =~ /^main::.*::$/) { | |||
| 147 | $pkg = "main$pkg" if $pkg =~ /^::/; | |||
| 148 | $pkg = "main::$pkg" unless $pkg =~ /^main::/; | |||
| 149 | $pkg .= '::' unless $pkg =~ /::$/; | |||
| 150 | } | |||
| 151 | ||||
| 152 | my($stem, $leaf) = $pkg =~ m/(.*::)(\w+::)$/; | |||
| 153 | my $stem_symtab = *{$stem}{HASH}; | |||
| 154 | return unless defined $stem_symtab and exists $stem_symtab->{$leaf}; | |||
| 155 | ||||
| 156 | ||||
| 157 | # free all the symbols in the package | |||
| 158 | ||||
| 159 | my $leaf_symtab = *{$stem_symtab->{$leaf}}{HASH}; | |||
| 160 | foreach my $name (keys %$leaf_symtab) { | |||
| 161 | undef *{$pkg . $name}; | |||
| 162 | } | |||
| 163 | ||||
| 164 | # delete the symbol table | |||
| 165 | ||||
| 166 | %$leaf_symtab = (); | |||
| 167 | delete $stem_symtab->{$leaf}; | |||
| 168 | } | |||
| 169 | ||||
| 170 | 1 | 1.1e-5 | 1.1e-5 | 1; |