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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