/* REXX */ ADDRESS ISREDIT; "MACRO NOPROCESS"; "(THEN) = LINENUM .ZF"   
"(ELSE) = LINENUM .ZL"; DO IF = THEN TO ELSE; "(WORD) = LINE (IF)"      
PARSE.IF = REVERSE(WORD); END; EXIT = 0; DO IF = ELSE TO THEN BY -1     
EXIT = EXIT + 1; SUBSTR = PARSE.IF; "LINE" EXIT "= (SUBSTR)"; END; EXIT