| Take the next Op argument, returning null if the end
of the arguments has been reached -- essentially a tokenizer for
Ops.
For example, consider "(a (b) (c (d (e)) f)". Remove all the "("s
and replace the ")"s with null to yield:
"a b null c d e null null f null"
This would be the result of many calls to nextOp, with any
further calls returning null.
Future: Maybe create real AST? Currently can get away with simple
nextOp pattern.
|