I've seen how XOR-3-SAT is efficiently solvable (for instance, see the "XOR-satisfiability" section in the Wikipedia entry for Boolean satisfiability problem).
I'm wondering a basic question: Is XOR-k-SAT efficiently solvable, for formulas with varying amounts of literals per clause?
I'd really like to know if we can increase the amounts of literals per clause beyond 3, and if we can have mixed clause lengths.