Repeats

A repeat is similar to a macro, but it cannot take arguments. Instead after a .rep directive, the preprocessor expects a number of times for the tokens inside to be repeated. A repeat block is ended with a .endrep directive.

Simple Example

.rep 5
    push 0
.endrep

This would expand to the following:

push 0
push 0
push 0
push 0
push 0

Number of Iterations

You can get access to the current iteration number by specifying either &0 or &1. The only difference between them being that &0 will start at 0, and &1 will start at 1.

.rep 5
    push &0
.endrep

This would expand to the following:

push 0
push 1
push 2
push 4
push 4

Meanwhile

.rep 5
    push &1
.endrep

Would expand to the following:

push 1
push 2
push 3
push 4
push 5

This is just meant to be a quality of life improvement, as you can always perform arithmetic on the result:

.rep 5
    push &0 + 3
.endrep

push 3
push 4
push 5
push 6
push 7