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# ?X #= ?Y

X is equal to Y.

?X
  A linear term.
?Y
  A linear term.

## Description

This constraints states that the two linear terms are equal. It is activated whenever the maximum or minimum of a domain variable is updated that might require updating other domains. When propagating domain updates, the system takes into account only maximum and minimum values of the whole domain and makes sure that these values are consistent with those of other domain variables.

If one of the arguments is a non-linear polynomial, this predicate delays until it becomes linear.

### Fail Conditions

Fails if the two linear terms have a different value.

### Resatisfiable

No.

## See Also

:: / 2, #:: / 2, ## / 2