This macro is a repetition construct.  If two 
seqs are (
a)(
b)(
c) 
			and (
x)(
y)(
z), this macro will produce the following 
			sequence:
			
				macro(r, (a)(x)) macro(r, (a)(y))
				macro(r, (a)(z)) \
				
				macro(r, (b)(x)) macro(r, (b)(y))
				macro(r, (b)(z)) \
				
				macro(r, (c)(x)) macro(r, (c)(y))
				macro(r, (c)(z))