
var(?Var)

   Succeeds if Var is a variable or an attributed variable.



Arguments
   Var                 Prolog term.

Type
   Type Testing

Description
   Used to test whether Var is a variable or an attributed variable.  The
   difference between var/1 and free/1 is that var/1 succeeds on attributed
   variables as well.


   var/1 could be defined as



    var(X) :- free(X).
    var(X) :- meta(X).



Modes and Determinism
   var(?) is semidet

Fail Conditions
   Fails if Var is instantiated

Examples
   
Success:
      var(X).
      var(_abc).
      var(_).
      var(X{a}).
      suspend:(X>0), var(X).

Fail:
      var(atom).
      var('Abc').





See Also
   free / 1, meta / 1, nonground / 1, nonvar / 1, type_of / 2
