Autovivification - File and Directory Handles

File and Directory Handles

Perl 5.6.1 and newer support autovivification of file and directory handles. Calling open on an undefined variable will set it to a filehandle. According to perl561delta, "his largely eliminates the need for typeglobs when opening filehandles that must be passed around, as in the following example:

for my $file ( qw(this.conf that.conf) ) { my $fin = open_or_throw('<', $file); process_conf( $fin ); # no close needed } use Carp; sub open_or_throw { my ($mode, $filename) = @_; open my $h, $mode, $filename or croak "Could not open '$filename': $!"; return $h; }

Read more about this topic:  Autovivification

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