By looking at the possible values of the condition.

I have a case where visiting has a side effect that I want to avoid.
Also spares work.

This options enables to generate jacobian apply methods regardless
of the `matrix_free` option. If `matrix_free` is set to true,
`generate_jacobian_apply` is also set to true. This option replaces
`matrix_free` in all contexts except in the selection of the solver.