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=>(+ConX,+ConY,Bool)

Bool is the reified truth of constraint ConX implying the truth of ConY.
ConX
Constraint
ConY
Constraint
Bool
Reified truth value of the constraint

Description

Equivalent to BX #= (ConX), BY #= (ConY), Bool #= (BX #=< BY)

The two constraints are reified in such a way that Bool is true if ConX being true implies that ConY must also be true. ConX and ConY must be constraints that have a corresponding reified form.

ConsistencyModule is the optional module specification to give the consistency level for the propagation for this constraint: gfd_bc for bounds consistency, and gfd_gac for domain (generalised arc) consistency.

This constraint is implemented using Gecode's MiniModel's rel() for both integer and boolean expressions, with sub-expressions/constraints not supported by MiniModel factored out and posted as auxiliary constraints.

A more restricted version of this constraint is defined in the global constraint catalog as 'imply', in that the reified truth value is the logical implication of 0/1 variables rather than constraints.

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

See Also

=> / 2, neg / 2, or / 3, xor / 3, and / 3, <=> / 3, ic : => / 3, suspend : => / 3