Don't forget the basic debugging step of printing your things to check if they are what you think they are:

my $re1=qr/foo$/;  
my $re2=qr/foo$/m;
my $re3=qr/foo$/s;
$,="\t"; $\="\n";  # just for output
print qr/$re1/, qr/$re1/m, qr/$re1/s;
print qr/$re2/, qr/$re2/m, qr/$re2/s;
print qr/$re3/, qr/$re3/m, qr/$re3/s;
__END__
(?^:foo$)       (?^:foo$)       (?^:foo$)
(?^m:foo$)      (?^m:foo$)      (?^m:foo$)
(?^s:foo$)      (?^s:foo$)      (?^s:foo$)

[download]

So that means...

my $re1=qr/foo$/;
print $re1, "\n";
print "foo\\nbar\\n =~ \/$re1\/ \t";
print "foo\nbar\n" =~ /$re1/ ?"true":"false"; print "\n";
print "foo\\nbar\\n =~ \/$re1\/m \t";
print "foo\nbar\n" =~ /$re1/m ?"true":"false"; print "\n";
my $re2=qr/foo$/m;
print $re2, "\n";
print "foo\\nbar\\n =~ \/$re2\/ \t";
print "foo\nbar\n" =~ /$re2/ ?"true":"false"; print "\n";
print "foo\\nbar\\n =~ \/$re2\/m \t";
print "foo\nbar\n" =~ /$re2/m ?"true":"false"; print "\n";
__END__
(?^:foo$)
foo\nbar\n =~ /(?^:foo$)/       false
foo\nbar\n =~ /(?^:foo$)/m      false
(?^m:foo$)
foo\nbar\n =~ /(?^m:foo$)/      true
foo\nbar\n =~ /(?^m:foo$)/m     true

[download]

(I haven't yet found the relevant bit of documentation that makes this behavior clear.)

In reply to Re: /s and /m don't seem to be doing anything by Anonymous Monk
in thread /s and /m don't seem to be doing anything by sciguy

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