Actually, '__PACKAGE__' and '__LINE__' [...] are special compiler directives. [...] They're NOT variables, hence they don't fall under strict's purview, nor any other purview, for that matter.

__PACKAGE__ doesn't bypass strict because it is some "special" "non-variable". It gets past strict because it is a compile-time constant (as I discussed in the thread that introduced this topic, self-referent hash for your packages).

Some more examples:

#!/usr/bin/perl -w
my @strictures;
BEGIN {
    require strict;
    if(  ! grep /-v/, @ARGV  ) {
        @strictures= "refs";
    }
}
use strict @strictures;
sub name1() { return "Foo::Bar" }
sub name2 { return "Foo::Bar" }

"Foo::Bar"->{key}= "value";
# No error

print name1->{key},$/;
# No error, prints "value"

eval {

    print name2->{key},$/       # Fatal run-time error
    # Can't use string ("Foo::Bar") as a HASH ref while "strict refs"

}   or  warn $@;
{
    package Foo::Bar;
    print __PACKAGE__->{key},$/;
    # No error, prints "value"
}

eval q{
    sub name3() { return "Foo" }
    sub name4 { return "Foo" }

    "Foo"->{key}= "bar";
    # If only strict 'refs', then prints "bar" w/ no errors
    # (-v)Global symbol "%Foo" requires explicit package name

    print name3->{key},$/;
    # If only strict 'refs', then prints "bar" w/ no errors
    # (-v)Global symbol "%Foo" requires explicit package name

    eval {

        print name4->{key},$/;
        # Can't use string ("Foo") as a HASH ref while "strict refs"

    }   or  warn "Line ",__LINE__,": $@";
    eval q{
        package Foo;

        print __PACKAGE__->{key},$/;
        # Use of uninitialized value in print

        1;
    }   or  warn "Line ",__LINE__,": $@";
}   or  warn "Line ",__LINE__,": $@";
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• Compile-time string contants that contain "::" can be used as symbolic references even under use strict "refs".
• Compile-time string contants that don't contain "::" generate a fatal "Global symbol requires explicit package" error under use strict "vars".
• The (horrid) __PACKAGE__-> trick, when used in a package whose name contains no "::", fails under use strict "vars" and tries to access a hash whose name is __PACKAGE__."::".__PACKAGE__ (instead of the usual name of __PACKAGE__).

Which makes me swing more toward the opinion that compile-time constant strings getting past use strict "refs" is simply a bug (and should put one more nail in the coffin of this hack).

Update: BTW, the reason that compile-time string constants get past use strict "refs", is (as I suspected) because the resulting code gets compiled as if the string were entered "bare":

perl -MO=Deparse -e "'Foo'->{key}= 'value'"
$Foo{'key'} = 'value';
-e syntax OK
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