Attribute Structure

Ranged variables are implemented as attributed variables. The attribute contains the following fields:

type

specifies the variable type, either integer or real.

lo

the smallest value the variable can assume

hi

the largest value the variable can assume

wake_lo

list of goals to be woken on lower bound change

wake_hi

list of goals to be woken on upper bound change

Type and bounds are accessed through the predicates described above. Goals can be delayed on the waking lists using the suspend/3 predicate, for example:

[eclipse 13]: X::0.0..5.5, suspend(writeln(change), 3, X->wake_lo), lwb(X,1).
change
X = X{1.0 .. 5.5}
yes.