merge.pl file_1 a,b,c file_2 d,e,f

##</code><code>##

file_1 a,b,c

##</code><code>##

keys = "a", "b", "c"

##</code><code>##

key values = /$aref_a, /$aref_b, /$aref_c

##</code><code>##

keys = "d", "e", "f"

##</code><code>##

key values = /$aref_d, /$aref_e, /$aref_f