Hello,

Consider this little program:

-------------------------------------------------------------- program main(input,output); var o, z: set of 1..15; begin o := [1]; z := []; if o < z then writeln('o < z'); if o <= z then writeln('o <= z'); if o = z then writeln('o = z'); if o <> z then writeln('o <> z'); if o >= z then writeln('o >= z'); if o > z then writeln('o > z'); if z < o then writeln('z < o'); if z <= o then writeln('z <= o'); if z = o then writeln('z = o'); if z <> o then writeln('z <> o'); if z >= o then writeln('z >= o'); if z > o then writeln('z > o'); if o < o then writeln('o < o'); if o <= o then writeln('o <= o'); if o = o then writeln('o = o'); if o <> o then writeln('o <> o'); if o >= o then writeln('o >= o'); if o > o then writeln('o > o'); if z < z then writeln('z < z'); if z <= z then writeln('z <= z'); if z = z then writeln('z = z'); if z <> z then writeln('z <> z'); if z >= z then writeln('z >= z'); if z > z then writeln('z > z'); end. --------------------------------------------------------------

GPC fails to compile this:

t19.p: In function Program_Main': t19.p:7: invalid operands to binary < t19.p:17: invalid operands to binary > t19.p:19: invalid operands to binary < t19.p:29: invalid operands to binary > t19.p:31: invalid operands to binary < t19.p:41: invalid operands to binary > t19.p:43: invalid operands to binary < t19.p:53: invalid operands to binary >

ISO 7185 sec. 6.7.1 suggests that this should work.

The correct output should be:

o <> z o >= z o > z z < o z <= o z <> o o <= o o = o o >= o z <= z z = z z >= z

Greetings, JanJaap

--- The nice thing about standards is that there are so many to choose from - Andrew Tanenbaum