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# <ConsistencyModule:> all_eq(?Collection,?Y)

Constrains Collection to be equal to Y.

Collection
  Collection of integers or (domain) variables
Y
  An integer or (domain) variable (array notation accepted)

## Description

Constrains every element in Collection to be equal to Y.

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 known as arith (with the equal to relation) in the Global Constraint Catalog, and is implemented using Gecode's rel() constraint.

## Examples

    [eclipse 51]: all_eq([1,2,3,5], X).     % fail

    [eclipse 52]: all_eq([1,1,1,1], X).

    X = 1

    [eclipse 53]: [X,Y] :: 0..10, Z :: 9..15, all_eq([X,Y,Z], A).

    X = X{[9, 10]}
    Y = Y{[9, 10]}
    Z = Z{[9, 10]}
    A = A{[9, 10]}

## See Also

#=< / 2, all_le / 2, all_gt / 2, all_ge / 2, all_lt / 2, all_ne / 2