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10.2.3 Java Location Values

When the directive %locations is used, the Java parser supports location tracking, see Locations Overview. An auxiliary user-defined class defines a position, a single point in a file; Bison itself defines a class representing a location, a range composed of a pair of positions (possibly spanning several files). The location class is an inner class of the parser; the name is Location by default, and may also be renamed using %define location_type "class-name.

The location class treats the position as a completely opaque value. By default, the class name is Position, but this can be changed with %define position_type "class-name". This class must be supplied by the user.

— Instance Variable of Location: Position begin
— Instance Variable of Location: Position end

The first, inclusive, position of the range, and the first beyond.

— Constructor on Location: Location (Position loc)

Create a Location denoting an empty range located at a given point.

— Constructor on Location: Location (Position begin, Position end)

Create a Location from the endpoints of the range.

— Method on Location: String toString ()

Prints the range represented by the location. For this to work properly, the position class should override the equals and toString methods appropriately.