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# <ConsistencyModule:> +ConX or +ConY

At least one of the constraints ConX or ConY must be true.

ConX
  Constraint
ConY
  Constraint

## Description

Equivalent to BX #= (ConX), BY #= (ConY), BX + BY #>= 1

The two constraints are reified in such a way that at least one must 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.

### Modules

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

## See Also

or / 3, neg / 1, xor / 2, and / 2, => / 2, <=> / 2, suspend : or / 2, ic : or / 2