NewActive creates a new parser based on the given parser and tokens.

NewIterator creates a new iterator over the results of an active parser.

NewParseTree creates a new parse tree from a token.

NewUnsupportedValue creates a new errors.Err error with the code InvalidOperation and the message "value of <expected> is not a supported <kind> type".

ErrExhausted occurs when an iterator is exhausted.

Active is the active parser.

Iterator is an iterator over the results of an active parser.

ParseTree the parse tree output by the parser.

Result is the result of an evaluation.