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# constraints_number(?Var, ?N)

The number of constraints and suspended goals associated with the variable
Var is N.
*?Var*
- Prolog term
*?N*
- Variable or integer

## Description

N is the number of constraints and suspended goals currently attached to
the variable Var. Note that this number may not correspond to the exact
number of different constraints attached to Var, as goals in different
suspending lists are counted separately. This predicate is often used
when looking for the most or least constrained variable from a set of
domain variables. If Var is instantiated, N is bound to a very large
integer, if Var is a free variable, N is zero.

### Fail Conditions

None.
### Resatisfiable

No.
## See Also

:: / 2, #:: / 2, deleteff / 3, deleteffc / 3