Re: accessing stashes

You can do that with the symbol table, but using defined and exists is cleaner.

#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

{   package My;
    sub one { print "123"; }
    sub two;
}

say ${My::}{one};              # *My::one
say ${My::}{two};              # -1
say ${My::}{three};            #

say defined *My::one{CODE};    # 1
say defined *My::two{CODE};    # 1
say defined *My::three{CODE};  # 

say exists &My::one;           # 1
say exists &My::two;           # 1
say exists &My::three;         # 

say defined &My::one;          # 1
say defined &My::two;          #
say defined &My::three;        #
[download]

Update: added the first paragraph of says.

Update 2: Interestingly, a forward declared sub with prototypes returns the prototypes with the first syntax:

sub four (&@);
# ...
say ${My::}{four};             # &@
[download]

Update 3: ... unless you add an attribute, too, which makes it output the glob name.

sub five (&@) :method;
say ${My::}{five};             # *My::five
[download]

Update 4: The -1 is printed only if you remove all other mentions of My::three, otherwise *My::three is printed.

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

Comment on Re: accessing stashes Select or Download Code

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Re^2: accessing stashes by ikegami (Patriarch) on Mar 01, 2019 at 19:12 UTC
`${hash}{foo} ${Pkg::}{foo}` [download] are weird ways of writing `$hash{foo} $Pkg::{foo}` [download]	[reply] [d/l] [select]
Re^2: accessing stashes by morgon (Priest) on Mar 01, 2019 at 18:45 UTC
That comes close, but I want something like this (the code below does NOT work): `use strict; sub hubba { } for my $symbol qw(hubba bubba) { print "$_: "; print defined *My::$symbol{CODE} ? "yep": "nope"; print "\n"; }` [download] That should print `hubba: yep bubba: nope` [download] How can I do that?	[reply] [d/l] [select]
Re^3: accessing stashes by ikegami (Patriarch) on Mar 01, 2019 at 19:14 UTC
`$My::{$symbol}` returns a glob. `NAME{SLOT}` accesses a glob's slot. `BLOCK{SLOT}` accesses a glob's slot. `$NAME{SLOT}` accesses a glob's slot. `EXPR->{SLOT}` accesses a glob's slot.^[1] So, `my $glob = $My::{$symbol}; $glob && { $glob }{CODE} $glob && $glob{CODE} $glob && $glob->*{CODE}` [download] Requires Perl 5.24+. Available in Perl 5.20+ by adding both `use feature qw( postderef );` and `no warnings qw( experimental::postderef );`, or by adding `use experimental qw( postderef );`.	[reply] [d/l] [select]
Re^4: accessing stashes by ikegami (Patriarch) on Mar 01, 2019 at 19:52 UTC
Something changed in 5.22. `$My::{$symbol}` can return a code reference or `-1` instead of a glob. The following is therefore needed: `sub get_code_ref_by_fqn { # Fully qualified name my ($fqn) = @_; my @pkg_name_parts = split /::/, $fqn; my $symbol = pop(@pkg_name_parts); my $pkg = \%::; for (@pkg_name_parts) { $pkg = $pkg->{$_.'::'} or return undef; } my $glob_or_code = $pkg->{$symbol} or return undef; return $glob_or_code if ref($glob_or_code); return undef if ref(\$glob_or_code) ne 'GLOB'; return *$glob_or_code{CODE}; }` [download] But you know what, let's just leave those dirty details to Perl. `sub get_code_ref_by_fqn { # Fully qualified name my ($fqn) = @_; no strict qw( refs ); return undef if !defined(&$fqn); return \&$fqn; }` [download] Above tested using `use 5.012; use warnings; sub Foo::Bar::y; sub Foo::Bar::z { } say get_code_ref_by_fqn('Foo::Bar::x') // '[undef]'; say get_code_ref_by_fqn('Foo::Bar::y') // '[undef]'; say get_code_ref_by_fqn('Foo::Bar::z') // '[undef]';` [download]	[reply] [d/l] [select]
Re^4: accessing stashes by morgon (Priest) on Mar 01, 2019 at 19:25 UTC
This is exactly what I was looking for - would you be so kind to rewrite my script above with your syntax (am interested in package "main") as I seem to be too drunk to do it myself and my attempts don't compile...	[reply]
Re^5: accessing stashes by ikegami (Patriarch) on Mar 01, 2019 at 19:28 UTC
Re^6: accessing stashes by morgon (Priest) on Mar 01, 2019 at 19:35 UTC
Some notes below your chosen depth have not been shown here


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