Wait, I am sorry, I confused it with the Wikipedia loader. There are not redirect definitions in this one.

    DEFINE ngramGenerator pignlproc.helpers.RestrictedNGramGenerator('$MAX_NGRAM_LENGTH', '', '$LOCALE');

Yes, this is the way it was used in names_and_entites_low_memory.pig, which was exactly the same file except for the changed call to the RestrictedNGramGenerator class.