# [plt-scheme] How to abstract in this situation

This follows on from the word permutations problem I posted recently.
Case 1
Generate all word permutations from an alphabet of length n where the
alphabet can contain letters of length i and i can be > 1.
Case 2
A variation to generate all permutations of words of length n or less.
An interesting case is if your alphabet is {"ab" "ba"} then you will
never be able to generate a word of length n where n is odd.
I ended up with 2 variations of the programs that differ in how they
handle the terminating condition.
Case 1
(let this and lambda that etc
(cond
[(= x y) currentcomputedvalue]
[else (recurse currentcomputedvalue)
Case 2
(let this and lambda that etc
(cond
[(> x y) startingvalue]
[(= x y) currentcomputedvalue]
[else append (filter startingvalue) (recurse currentcomputedvalue)])
The "let this and lambda that" bits are identical in both programs, as
are the first cond line in Case 1 and the 2nd cond line in Case 2.
In seeking to combine them is there a way I can do better than the
obvious pass a parameter denoting which case I am running and then
If Case1
code for Case1
code for Case2