It's technically the dereference of a symbolic reference that's not allowed. However, there is a (documented) exception:

\&$sub_name
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This means that while

$sub_name->()
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isn't allowed,

(\&$sub_name)->()
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is allowed.

($invocant->$method_name() is also allowed under strict.)

It's technically the dereference of a symbolic reference that's not allowed.

Is there another case where you would call a variable a symbolic reference when it's not being dereferenced? With eval or when accessing a value through the symbols table?

You're right about those two exceptions, at least the exceptions are complex enough that beginners shouldn't use them by accident.

> However, there is an exception:

More there are:

use strict;
use warnings;


sub tst {
    warn "tst($_[0]) called\n"
}

my $symbol="tst";


($::{$symbol})->(1);

&{$::{$symbol}}(2);

(main->can($symbol))->(3);

&{main->can($symbol)}(4);
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C:/Perl_524/bin\perl.exe  d:/exp/symbolic_references.pl 
tst(1) called
tst(2) called
tst(3) called
tst(4) called
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NB:

• $::{...} is a shortcut for STASH lookup $main::{...} and returns a type-glob
• ->can(...) returns a coderef

  Cheers Rolf
  _{(addicted to the Perl Programming Language :)
  Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}

Those aren't really exceptions. Strict refs is only meant to stop you from accidentally using symbolic refs. (After all, you can always turn it off strict refs off if you want to use symbolic refs intentionally.) %:: and can only take symbol names, so they can't accidentally be used incorrectly.

Here is another exception, no complaints:

use strict;
use warnings;
sub asub { print "heee\n"; }

my $x = 'asub';
main->$x();
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bw, bliako

Not really an exception IMHO because asub is a "method" of the main class/package, so the  -> invocant works as documented.

---

Give a man a fish:  <%-{-{-{-<

I would like to call it a method too but where is the reference to the main class/package "object" as the first parameter when calling asub() (a-la $obj->asub() which sends $obj as the first parameter)? Also, I would like to call it a "static method" but this: main::$x() does not work. Too many exceptions! (Edit: could n't resist the pun of too many anomalies :) )

bw, bliako