Hi all,

The following subroutine returns its argument with any leading newlines removed: 

sub xxx {
my $s = shift;
$s =~ s/^\n+//;
$s;
}

[download]
However, if this function is called from the replacement part of a s///em, the /m semantics is carried over, and internal newlines will be deleted. 
#!/usr/bin/perl

use strict;
use warnings;
no warnings qw /syntax/;

use Test::More tests => 1;

#
# Delete any leading newlines.
#
sub xxx {
my $s = shift;
$s =~ s/^\n+//;
$s;
}

my $a = "A\n\nB"; $a =~ s/([\s\w]+)/xxx $1/e;
my $b = "A\n\nB"; $b =~ s/([\s\w]+)/xxx $1/em;

is ($b, $a);

__END__

1..1
not ok 1
# Failed test (eep at line 21)
# got: 'A
# B'
# expected: 'A
#
# B'
# Looks like you failed 1 test of 1.

[download]

"Keep pouring your ideas"

2006-10-07 Unapproved by planetscape once evidence of habitual plagiarism uncovered.

In reply to s/PATTERN/func()/em leaks /m into func() by jesuashok

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