how to divide expression into two by element?

[acekingke]

I have a question, given a '(a b c d) , I want use 'b to divide the list to two parts, as '(a ) , '(c d)

[Kodiologist]

=> (setv x '(a b c d))
=> (cut x (.index x 'b))
'(a)
=> (cut x (+ 1 (.index x 'b)) None)
'(c d)

[acekingke]

Thank you very much, it works