question: get the 0-based line number of this line . concode_field_sep String fileName concode_elem_sep int lineIdx concode_elem_sep Set<LineHighlight> listeners concode_elem_sep Position pos concode_elem_sep Document doc concode_field_sep void removeUpdate concode_elem_sep String fileName concode_elem_sep void updatePosition concode_elem_sep void editEvent concode_elem_sep void removeListener concode_elem_sep int nonWhiteSpaceOffset concode_elem_sep void stopTracking concode_elem_sep void startTracking concode_elem_sep int hashCode concode_elem_sep boolean equals concode_elem_sep String toString concode_elem_sep void changedUpdate concode_elem_sep void addListener concode_elem_sep void insertUpdate
target: int function ( ) { return lineIdx ; }