a three-branch if/else-if/else chain lowers to a single flat
conditional.

<<<

classify = fun (n int) int {
    if n < 0 {
        return -1
    } else if n == 0 {
        return 0
    } else {
        return 1
    }
}

>>>

(unit
	(types
		(type 0 int primitive)
		(type 1 uint primitive)
		(type 2 bool primitive)
		(type 3 string primitive)
		(type 4 float primitive)
		(type 5 byte primitive)
		(type 6 ascii primitive)
		(type 7 void primitive))
	(functions
		(function 0 classify (returns (ref int)) (param n (ref int)) (block
			(conditional (when (expr (binary < (expr (name n)) (expr 0)))) (block
				(return (expr (unary - (expr 1))))
			) (when (expr (binary == (expr (name n)) (expr 0)))) (block
				(return (expr 0))
			) (else) (block
				(return (expr 1))
			))
		)))
	(emission_order 0 1 2 3 4 5 6 7))