Perl is a free-form language when comes to syntax layout. You don't need special operator to break your statement into as many lines as you like, or as your eyes can handle. But I'm not going to write a subroutine with that many arguments. I either use hash (for using named parameters instead of positional parameters), or break up the subroutine.

The same applies with string. Just type in the long string, and break it at your will.

my $str = "This string is not that long
but I break it anyway becauase
Perl allows me to do so and I just want to
do it this way. But remember, there will be
newlines inserted between
lines";
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Or, if you like, use the concatenation operator:

my $str = "This string is not that long" .
          " but I break it anyway becauase" .
          " Perl allows me to do so and I just want to" .
          " do it this way. But remember, there will not" .
          " be newlines inserted between lines" .
          " unless I say it explicitly," .
          " like\n" .
          " this";
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Many Perl programmers, however, prefer to use here-doc syntax:

my $str = <<EOF;
This string is not that long
but I break it anyway becauase
Perl allows me to do so and I just want to
do it this way. But remember, there will be
newlines inserted between
lines. I can also put $some ($variables) here.
EOF
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