! /^\|$/;
  $this !~ /^\|$/;
  ord($this) != 124;
  ord($this) != 0x7c;
  ord($this) != 0174;
  seek(THIS, 2, 0);
  `ls -l $this` !~ /^p/;
  ! -p _;
  return ! -p _;
  -p _ && die;
  die if -p _;
  return 1 unless -p _;
  use Test::More; isnt($this, 'pipe', 'Magritte check');
  $this ne 'a|';
  next unless /^(\w)\|$/; next if $1 eq 'a';
  open(my $fh, "a|"); while(<$fh>) { die if /\Q$this\E/; }
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