A Super Search on “Operation """"” finds this 2009 thread: overload op requires stringify overload ?? Applying Bloodnok’s “fix of sorts” —

#! perl --
BEGIN {
    package OOO;
    sub new      { my( $pkg, $path ) = @_; bless \$path, $pkg; }
    sub filetest { warn "its fake @_\n"; 'fake' }
    use overload '-X' => \&filetest, fallback => 1;
    $INC{'OOO.pm'} = __FILE__;
}
use strict; use warnings;
use OOO;
-f OOO->new('.');
[download]

gives:

22:15 >perl 804_SoPW.pl
its fake OOO=SCALAR(0x1c15434) f

22:19 >
[download]

Is that what you were wanting?

Anyway, hope it helps,

It appears ++Athanasius has provided a solution. Here's some additional documentation:

• The overload pragma has extensive, general information.
• The "Special Keys for use overload" section is specific to Athanasius's solution.