I have not used bareword filehandles since lexical filehandles were made available. While upgrading a Perl program from bareword filehandles to lexical filehandles I noticed an inconsistency using heredocs. Bareword filehandles in heredocs work fine with a space following the "<<", but lexical filehandles in heredocs generate an error with a space following the "<<".

Since bareword filehandles are due to be deprecated, this may not be a pressing issue. I'm posting this so that others who may run into the same situation do not have to spend the debugging time tracking down this inconsistency.

The following code shows the inconsistency: 

#!/usr/bin/perl
use strict;
use warnings;

my $HFILE;
my $hfile = 'foo.txt';

# GOOD
#####################################################################
# Bareword filehandle works with space following heredoc "<<".
#####################################################################
open(HFILE, '>', $hfile) or die "Error opening help file $hfile: $!\n"
+;
print HFILE << "EOT";
Usage: foo.pl
Options:
--------
-h          Display help information.
EOT

# BAD
#####################################################################
# Lexical filehandle does NOT work with space following heredoc "<<".
#####################################################################
open($HFILE, '>', $hfile) or die "Error opening help file $hfile: $!\n
+";
print $HFILE << "EOT";
Usage: foo.pl
Options:
--------
-h          Display help information.
EOT

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In reply to Heredoc Inconsistency: Bareword Filehandle vs Lexical Filehandle by roho

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