| option | |
| ------ | |
| Provides an option that the user can optionally select. | |
| :: | |
| option(<option_variable> "help string describing option" | |
| [initial value]) | |
| Provide an option for the user to select as ``ON`` or ``OFF``. If no | |
| initial value is provided, ``OFF`` is used. If the option is already | |
| set as a normal variable then the command does nothing | |
| (see policy :policy:`CMP0077`). | |
| If you have options that depend on the values of other options, see | |
| the module help for :module:`CMakeDependentOption`. |