Miscellaneous

Now that we have introduced many of the aspects of KASM and inner workings of kOS, this page will serve as a quick reference for implementing various things.

If statements

Let’s say we had the variable $x, and wanted to basically do:

IF X > 1 {
    PRINT "IF".
} ELSE {
    PRINT "ELSE".
}

The KASM implementation would be:

	push "$x"
	push 1
	cgt         ; x > 1
	bfa .else
	push @
	push "IF"
	call #, "print()"
	pop
	jmp .if_end
    .else:
	push @
	push "ELSE"
	call #, "print()"
	pop
    .if_end:
	...

While loop

Let’s say we wanted to implement the following while loop (the inverse of an UNITL loop):

while SHIP:ALTITUDE < 70000 {
    wait 0.
}

This would be implemented in KASM as:

.loop:
    push 0
    wait
    push "$ship"
    gmb "altitude"
    push 70000
    clt            ; SHIP:ALTITUDE < 70000
    btr .loop

For loop

Example code in C style:

for (int i = 0; i < 10; i++) {
    PRINT i.
}

In KerboScript:

FROM {local i is 0.} UNTIL !(i < 10) STEP {SET i to i + 1.} DO {
    PRINT i.
}

KASM (using the stack):

push 0
.loop:
    dup
    push 10
    clt
    bfa .loop_end
    dup
    push @
    swap
    call #, "print()"
    pop
    push 1
    add
    jmp .loop
.loop_end:
    ...

KASM (using a kOS variable $i):

bscp 1, 0
push 0
stol "$i"
.loop:
    push "$i"
    push 10
    clt
    bfa .loop_end
    push @
    push "$i"
    call #, "print()"
    pop
    push "$i"
    push 1
    add
    sto "$i"
    jmp .loop
.loop_end:
    escp 1