Qat: ...
e.g. d.g, pin*; ranges are [sz] [l-p], [!sz] (!!). Character classes: @ = [aeiou], # = consonant including y.
Words: > = word, < = reversed word, so e.g. s> are S prefix hooks. 7-9:x*a = length constraint (either bound can be omitted); /anagram or */letterbank; &|! intersect, union, or set-subtract constraints.
Equation solver: A-Z mean strings, constraints separated by ; force them to be words, e.g. cyclically permuted words are AB;BA, words that take a K to L misprint are AkB;AlB. ~A is reversed A. Different constraints: !=AB or !=A<B<C. Length constraints: |A|=3-7. Note that string variables are nonempty by default; add |A|=0- to override.