Hi folks,

I've recently started to follow some "best practices" recommended to me, and while converting s/// to s{}{}xms I came upon a strangeness:

perlport suggests using
s/$CR?$LF/\n/;

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to clean up input lines from strange operating systems, so I tried the following:
my $CR="\015";
my $LF="\012";
my $foo="unknown_os\n";
$foo =~ s{$CR?$LF}{\n}xms;
print $foo;

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This gives me:
? <-- HERE follows nothing in regex; marked by <-- HERE in m/
/ at -e line 4.

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Without the "x" this works fine.

So what gives?

I thought there was no problem using variables inside extended patterns, and couldn't find anything to the contrary in any documentation / web search either.

/|\

In reply to Variables in extended patterns? by flamewise

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