Select from List the variable Var which has the smallest lower domain bound,
and return the rest of the list.
-Var
A variable.
-Rest
A term unifying with a list of domain variables or integers.
+List
A list of domain variables or integers.
Description
This predicate is used in labeling procedures. Especially when labeling
start times in scheduling problems, it is often a good strategy to start
with the earliest possible tasks, because fixing those will cause useful
bounds propagation on the start times of the other tasks. This predicate
selects from a list the variable with the smallest lower bound. Numbers
are treated as if they were variables with singleton domains.