From the CGI docs:

PRETTY-PRINTING HTML

By default, all the HTML produced by these functions comes out as one long line without carriage returns or indentation. This is yuck, but it does reduce the size of the documents by 10-20%. To get pretty-printed output, please use the CGI::Pretty manpage, a subclass contributed by Brian Paulsen.

use CGI::Pretty;
print "foo\n";
print "bar\n";
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Does what you mean.