How about instead of () you insert die("Deferred implementation can't be executed");.
Perhaps, but when I used it I just wanted a placeholder, not necessarily an abstract op (yes, I made that up ;) and I also have no idea how it will be implemented in perl6 (it may be described in p6l ... somewhere). Maybe we need YAO instead 
package bangbangbang;

use Filter::Simple;

FILTER_ONLY
  code => sub {
    s{ \s \Q!!!\E \s }
     { die("Deferred implementation can't be executed"); }gx
  };

q[ ichi ni san ];

[download]
And obligatory example usage 
use bangbangbang;

sub foo { !!! }
my $bar = sub { !!! };
sub baz { return !!! }

eval { foo()   } or warn "foo() - $@";
eval { &$bar() } or warn "bar() - $@";
eval { baz()   } or warn "baz() - $@";

__output__

foo() - Deferred implementation can't be executed at bbb_test.pl line 
+3.
bar() - Deferred implementation can't be executed at bbb_test.pl line 
+4.
baz() - Deferred implementation can't be executed at bbb_test.pl line 
+5.

[download]

HTH

_________
broquaint

In reply to Re: Re: the 'dot dot dot' operator by broquaint
in thread the 'dot dot dot' operator by broquaint

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