This is a repeated operation creating one triangle with each run of a macro. Macros are essential for C.a.R., since complicate constructions would not be possible without macros. In C.a.R., macros can perform rather complicate constructions, including computations.
To create a macro in C.a.R. is easy. First create a construction, depending on some basic objects. Then tell the program to make a macro out of it, using the basic objects as parameters and the construction as the target. When the macro is run, the parameters must be assigned to existing objects of the same type, and the macro creates the targets automatically.