How about this:

$_ = "   yes  \n   \n   \n    they    \n \n    will     \n\n\n";
s/^\s*?(?:\b(.*?)\s*?)?(\n)?$/$1$2/gm;
print;
__END__
% perl 443391.pl
yes


they

will

[download]

the lowliest monk

In reply to Re^4: trim leading & trailing whitespace by tlm
in thread trim leading & trailing whitespace by ady

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