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# nonground(?Term, -Variable)

Succeeds if Term is not a ground term and binds Variable to one of the
variables inside Term.
*Term*
- Prolog term.
*Variable*
- A variable.

## Description

Used to test whether Term is not ground i.e. whether it contains at
least one uninstantiated variable. The argument Variable is unified with one of
the variables inside Term, i.e. with one of the responsibles for its
non-groundness. When Term contains several variables, it is not
specified which one will be returned as Variable. As usual, attributed
variables are also considered variables.
This predicate can handle cyclic terms.

### Modes and Determinism

- nonground(?, -) is semidet

### Fail Conditions

Fails if Term is ground
## Examples

Success:
nonground(Term, V). % unifies V with Term
nonground(f(a,B,c), V). % unifies V with B
nonground([x,Y|Z], V). % unifies V with Y or Z
nonground(s(X{a}), V). % unifies V with X{a}
Fail:
nonground(atom, V).
nonground(likes(man, woman), V).

## See Also

nonground / 1, nonground / 3, nonvar / 1, var / 1