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3.2 Variables and macros useful in grammar actions.

— Variable: wisent-input

The last token read. This variable only has meaning in the scope of wisent-parse.

— Function: wisent-lexer

Obtain the next terminal in input.

— Function: wisent-region &rest positions

Return the start/end positions of the region including positions. Each element of positions is a pair (start-pos .  end-pos) or nil. The returned value is the pair (min-start-pos . max-end-pos) or nil if no positions are available.