R3 Parse: Can 'thru used with a charset?

I use 'thru with a charset, but it doesn't seem to work the way I want: >> word: charset [#"A" - #"Z"] == make bitset! #{00000000000000007FFFFFE0} >> parse "apple_NP" [thru word] == false In my mind the second evaluation should return a "true", I don't know why it is false?

"_" is not included in your charset. You could do: parse "apple_NP" [thru "_" any word]