Select Code to Download

my @phrases = qw( foo bar );
my $sentence = " foo bar ";
...
$sentence =~ s/(\s$phrases_pat\s)/#$1#/g;

print("$sentence\n");   # "# foo ## bar #"

...

...
$sentence =~ s/\s($phrases_pat)\s/#$1#/g;

print("$sentence\n");   # "#foo##bar#"