Kernel.defmacrop

You're seeing just the macro defmacrop, go back to Kernel module for more information.
Link to this macro

defmacrop(call, expr \\ nil)

View Source (macro)

Defines a private macro with the given name and body.

Private macros are only accessible from the same module in which they are defined.

Private macros must be defined before its usage.

Check defmacro/2 for more information, and check def/2 for rules on naming and default arguments.