# option

Provide an option that the user can optionally select.

    option(<variable> "<help_text>" [value])

Provides an option for the user to select as `ON` or `OFF`. If no initial `<value>` is provided, `OFF` is used. If `<variable>` is already set as a normal variable then the command does nothing (see policy `CMP0077`).

If you have options that depend on the values of other options, see the module help for `CMakeDependentOption`.