[eclipse-users] Newbie: not consecutive procedure clauses

From: Philippe de Rochambeau <phiroc_at_free.fr> Date: Sun, 7 Jan 2007 00:25:43 +0100 · This archive was generated by hypermail 2.2.0 : Thu Feb 02 2012 - 02:31:57 CET

Hello,

whenever I compile the following code from the book "Learn Prolog Now!",

wizard(ron).
hasWand(harry).
wizard(X):- hasBroom(X), hasWand(X).
quidditchPlayer(harry).
hasBroom(X) :- quidditchPlayer(X).

I get the following message,

*** procedure clauses are not consecutive: wizard / 1
         before line 6 in the file /Applications/eclipse/myscripts/ 
harry.pl
harry.pl   compiled traceable 116 bytes in 0.00 seconds

Yes (0.00s cpu)

Could someone please explain why my procedure clauses should be  
"consecutive"?

Many thanks.

Best regards,

Philippe