
deleteff(-Min, +List, -Rest)

   Pick minimum domain size element from a list (first fail principle)

Arguments
   Min                 Smallest list element in terms of domain size
   List                List of domain variables or constants
   Rest                Remaining list without smallest element

Type
   library(sd)

Description

	Extracts from a list of domain variables (or constants) the first
	element with the smallest domain. This element is returned as Min,
	and the remaining list without this element is returned as Rest.
	This predicate is useful for implementing the first-fail-principle
	in a search procedure, i.e. labeling the variable with the smallest
	domain first. E.g.
	
	labelingff(List) :-
		( deleteff(X, List, Rest) ->
		    indomain(X),
		    labelingff(Rest)
		;
		    true
		).
	


Fail Conditions
   List is empty

See Also
   get_domain_size / 2
