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• The any inst: | ||

• Abstract solver type declarations: | ||

• Solver type definitions: | ||

• Implementing solver types: | ||

• Solver types and negated contexts: |

Solver types are an experimental addition to the language supporting the
implementation of constraint solvers.
A program may place constraints on and between variables of a solver type,
limiting the values those variables may take on before they are actually bound.
For example, if `X`

and `Y`

are variables belonging to a constrained
integer solver type, we might place constraints upon them such that
`X > 3 + Y`

and `Y =< 7`

.
A later attempt to unify `Y`

with `10`

will fail (it would violate
the second constraint); similarly an attempt to unify `X`

with `5`

and `Y`

with `4`

would fail (it would violate the first constraint).