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.\" -*- mode: troff; coding: utf-8 -*-
.\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43)
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
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..
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.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>.
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.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el .ds Aq '
.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD. Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.\"
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.rr rF
.\" ========================================================================
.\"
.IX Title "Symbol 3pm"
.TH Symbol 3pm 2023-11-28 "perl v5.38.2" "Perl Programmers Reference Guide"
.\" For nroff, turn off justification. Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH NAME
Symbol \- manipulate Perl symbols and their names
.SH SYNOPSIS
.IX Header "SYNOPSIS"
.Vb 1
\& use Symbol;
\&
\& $sym = gensym;
\& open($sym, \*(Aq<\*(Aq, "filename");
\& $_ = <$sym>;
\& # etc.
\&
\& ungensym $sym; # no effect
\&
\& # replace *FOO{IO} handle but not $FOO, %FOO, etc.
\& *FOO = geniosym;
\&
\& print qualify("x"), "\en"; # "main::x"
\& print qualify("x", "FOO"), "\en"; # "FOO::x"
\& print qualify("BAR::x"), "\en"; # "BAR::x"
\& print qualify("BAR::x", "FOO"), "\en"; # "BAR::x"
\& print qualify("STDOUT", "FOO"), "\en"; # "main::STDOUT" (global)
\& print qualify(\e*x), "\en"; # returns \e*x
\& print qualify(\e*x, "FOO"), "\en"; # returns \e*x
\&
\& use strict refs;
\& print { qualify_to_ref $fh } "foo!\en";
\& $ref = qualify_to_ref $name, $pkg;
\&
\& use Symbol qw(delete_package);
\& delete_package(\*(AqFoo::Bar\*(Aq);
\& print "deleted\en" unless exists $Foo::{\*(AqBar::\*(Aq};
.Ve
.SH DESCRIPTION
.IX Header "DESCRIPTION"
\&\f(CW\*(C`Symbol::gensym\*(C'\fR creates an anonymous glob and returns a reference
to it. Such a glob reference can be used as a file or directory
handle.
.PP
For backward compatibility with older implementations that didn't
support anonymous globs, \f(CW\*(C`Symbol::ungensym\*(C'\fR is also provided.
But it doesn't do anything.
.PP
\&\f(CW\*(C`Symbol::geniosym\*(C'\fR creates an anonymous IO handle. This can be
assigned into an existing glob without affecting the non-IO portions
of the glob.
.PP
\&\f(CW\*(C`Symbol::qualify\*(C'\fR turns unqualified symbol names into qualified
variable names (e.g. "myvar" \-> "MyPackage::myvar"). If it is given a
second parameter, \f(CW\*(C`qualify\*(C'\fR uses it as the default package;
otherwise, it uses the package of its caller. Regardless, global
variable names (e.g. "STDOUT", "ENV", "SIG") are always qualified with
"main::".
.PP
Qualification applies only to symbol names (strings). References are
left unchanged under the assumption that they are glob references,
which are qualified by their nature.
.PP
\&\f(CW\*(C`Symbol::qualify_to_ref\*(C'\fR is just like \f(CW\*(C`Symbol::qualify\*(C'\fR except that it
returns a glob ref rather than a symbol name, so you can use the result
even if \f(CW\*(C`use strict \*(Aqrefs\*(Aq\*(C'\fR is in effect.
.PP
\&\f(CW\*(C`Symbol::delete_package\*(C'\fR wipes out a whole package namespace. Note
this routine is not exported by default\-\-you may want to import it
explicitly.
.SH BUGS
.IX Header "BUGS"
\&\f(CW\*(C`Symbol::delete_package\*(C'\fR is a bit too powerful. It undefines every symbol that
lives in the specified package. Since perl, for performance reasons, does not
perform a symbol table lookup each time a function is called or a global
variable is accessed, some code that has already been loaded and that makes use
of symbols in package \f(CW\*(C`Foo\*(C'\fR may stop working after you delete \f(CW\*(C`Foo\*(C'\fR, even if
you reload the \f(CW\*(C`Foo\*(C'\fR module afterwards.
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