How abstract do you want it? 

ref($this) ne 'Pipe';
ref($_) ne 'Pipe';     # $_ is a topicaliser, so is "this" - thus, "th
+is" == "$_"
! UNIVERSAL::can($this, 'smoke');
$_->can('smoke');

[download]
Perl 6 ok? 
!.isa('Pipe');

[download]
Just wondering.

Update: Missed the ! on the perl6 code.

In reply to Re: This is not a pipe by Tanktalus
in thread This is not a pipe by TGI

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