smie-op-left
smie-op-left is an alias for `car' in `smie.el
'.
(smie-op-left LIST)
Return the car of LIST. If arg is nil, return nil.
Error if arg is not nil and not a cons cell. See also `car-safe'.
See Info node `(elisp)Cons Cells' for a discussion of related basic
Lisp concepts such as car, cdr, cons cell and list.