If you want to make this run a bit faster, and aren't worried about false positives on fringe cases (such as people adding non-standard attributes), you can simplify the test to 
  my $attr = shift;
  my @found = { grep /^on[A-Z]/ } keys %$attr;

[download]
This also "future proofs" the code against the possiblity of someone's browser adding yet another new event.

Update: D'oh. Make that   my @found = { grep /^on/ } keys %$attr; since the attributes all come back lower-case.

In reply to Re: Am I javascript or not? by dws
in thread Am I javascript or not? by boo_radley

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