+* We accept both forms of preprocessor if's: `#ifdef DEFINED` and `#if defined(DEFINED)`
+ * If you are not sure which to prefer use the `#if defined(DEFINED)` form.
+ * Do not change existing code from one style to the other, except when moving to a multiple condition `#if`.
+ * Do not put whitespace between `#` and `if`.
+ * When deciding how (or if) to indent directives keep these points in mind:
+ * Readability is more important than consistency.
+ * Follow the file's existing style. If the file is mixed follow the style that makes sense for the section you are modifying.
+ * When choosing to indent you can follow the indention level of the surrounding C code, or preprocessor directives can have their own indent level. Choose the style that best communicates the intent of your code.