BBC BASIC Programmers' Reference

by Jon Ripley, Richard Russell, January 2012

The FN_linenumber(!384) function returns the line number of the currently executing line of code as demonstrated below.

  12345 PRINT FN_linenumber(!384)
        END
 
        DEF FN_linenumber(E%)
        LOCAL P% : P% = PAGE
        WHILE ?P% AND P% + ?P% < E% P% += ?P% : ENDWHILE
        = (P%?2*256+P%?1)

Always pass !384 as the parameter to FN_linenumber, this interpreter internal variable is the pointer to (or within) currently-executing statement.