smie-backward-token-function

smie-backward-token-function is a variable defined in `smie.el'.
Its value is

smie-default-backward-token

• This variable may be risky if used as a file-local variable.

Documentation:
Function to scan backward the previous token.
Same calling convention as `smie-forward-token-function' except
it should move backward to the beginning of the previous token.