[eclipse-users] Q regarding mode declarations

Hi everybody,

I have a question regarding mode declarations.  Chapters 2 and 6.6 of the
ECLiPSEe User Manual explain modes.


Is it true that there can be at most one mode declaration per predicate
specification, i.e., pair of predicate name and arity?

I ask because many predifined predicates give two or more modes.  For
example the reference manual lists the following for append/3:

append(+, +, -)
append(-, -, +)


My guess is: Yes, there can be at most one mode declaration.  The modes
given in the manual are only to explain the different classes of determinism
of the predicate.

But then, do predifined predicates have mode declarations?  And what would
happen if I give two mode declarations for the same predicate?


Best,

Ulrich
-- 
Ulrich Scholz            

Personal Memory Group                   
European Media Laboratory GmbH