Don't try to replace self in a macro expansion since it's unlikely to be the desired behavior. A more explicit means of specifying what variables should be replaced in a quote expression is needed.

#{
	main <- {
		foo <- dict linear:
		foo set: "key1" "val1"
		foo set: "key2" "val2"
		foreach: foo :k :v {
			print: k . ", " . v . "\n"
		}

	}
}