60000 REM XREF 23-JUL-91 (C) A.K.JORDAN 63090 REM Tree node - format 1 63100 ' 0 = Pointer (subscript & byte#) to symbol in xref$() 63110 ' 1 = Left link (or 0) to another format 1 node 63120 ' 2 = Right link to another format 1 node 63130 ' 3 = Statement # of the first line containing the pointed symbol 63140 ' 4 = Link to a format 2 node. Also bit 13 set on an altered symbol 63150 REM Tree node - format 2 63160 ' 0,1,2,3 = Statement #'s of upto 4 lines containing the same symbol 63170 ' 4 = Link to another format 2 node 63180 ' Also bit n+10 is set if an altered symbol relates to stmt# n