I have a hash table HASH containing strings, and want to generate a string
for an equivalent Javascript variable JS from it e.g.

HASH = {'a' => 'A', 'b' => 'B'}

"var JS = { 'a' : 'A', 'b' : 'B' }"

I thought inject was just the ticket:

'var JS = {' +
  HASH.inject("") { |str, kv| str << "\n\t'#{kv[0]}' : #{kv[1]}, " } +
  "};"

But this puts a "," after the last item. Is there a simple alternative?

Thanks.