While doing some research on On bad habits related to $^L, I stumbled across this bit in the POD for IO::Handle:

See perlvar for complete descriptions of each of the following support
+ed "IO::Handle" methods.  All of them return the previous value of th
+e attribute and takes an optional single argument that when given wil
+l set the value.  If no argument is given the previous value is uncha
+nged (except for $io->autoflush will actually turn ON autoflush by de
+fault).

  $io->autoflush ( [BOOL] )                         $|
  $io->format_page_number( [NUM] )                  $%
  $io->format_lines_per_page( [NUM] )               $=
  $io->format_lines_left( [NUM] )                   $-
  $io->format_name( [STR] )                         $~
  $io->format_top_name( [STR] )                     $^
  $io->input_line_number( [NUM])                    $.

The following methods are not supported on a per-filehandle basis.

  IO::Handle->format_line_break_characters( [STR] ) $:
  IO::Handle->format_formfeed( [STR])               $^L
  IO::Handle->output_field_separator( [STR] )       $,
  IO::Handle->output_record_separator( [STR] )      $\
  IO::Handle->input_record_separator( [STR] )       $/
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I had been hoping to see that there was a per-filehandle setting for $^L; apparently $/ falls in the same category. My question is: is this due to some fundamental restriction of filehandles? If not, it would be nice to have more extensive per-filehandle attributes. I suppose this is "fixed" in Perl6...