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var_inc_violations(?X, +Delta)

Increment X's violation count by Delta
X
A a tentative variable
Delta
A number

Description

Increment X's violation count by Delta. X should be a variable with a tentative value. The initial violation count for every variable is 0.

Calling var_inc_violations/2 on a nonvariable has no effect and silently succeeds.

Modes and Determinism

Fail Conditions

Fails if X is a variable without tentative value

Examples

    ?- tent_set(X, 27), var_inc_violations(X, 3).
    X = X{27 -> 3}
    Yes (0.00s cpu)

    ?- tent_set(X, 27), var_inc_violations(X, 3), var_inc_violations(X, 1).
    X = X{27 -> 4}
    Yes (0.00s cpu)

    ?- tent_set(X, 27), var_inc_violations(X, 3), var_inc_violations(X, -1).
    X = X{27 -> 2}
    Yes (0.00s cpu)

    ?- var_inc_violations(foo, 3).
    Yes (0.00s cpu)

    ?- var_inc_violations(_, 3).
    No (0.00s cpu)

See Also

tent_set / 2, has_tent_value / 1, tent_get / 2, var_get_violations / 2