Not real sure why everyone posted regex solutions here, use substr and index. Much faster. 
while (<DATA>) {
    if ( ( my $p = index( $_, "#" ) ) > -1 ) { substr( $_, $p, -1, "" 
+) }
    next if /^\s*$/;
    print;
}
__DATA__
#comment
this is test#comment
#comment
this is test #comment
this is test #comment
this is test #comment

[download]
A regex in any form (split, s/// or m//) is overkill for this task. (Assuming of course that # can't appear in the real data)

Yves / DeMerphq
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In reply to Re: Support for hash comments on a line (Why use a regex at all?) by demerphq
in thread Support for hash comments on a line by c

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