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local variable(+Name, ?Init)
Creates the untyped non-logical variable Name.
- Name
- An atom.
- Init
- Any term
Description
   A non-logical variable with name Name (visible only in the
   caller module) is created.  Its value is initialised to Init.
   The contents of the variable persists across failures.
   The value of a non-logical variable can be changed with
   setval/2 and retrieved with getval/2.  Setting and retrieving terms
   from a non-logical variable involves copying the term each time. 
   In particular, if the term contains variables, they lose their
   identity and are replaced with fresh ones.
   Notes:
   Declaring a variable twice is silently accepted, and the second
   declaration is ignored.
Modes and Determinism
Exceptions
- (4) instantiation fault 
- Name is not instantiated.
- (5) type error 
- Name is not an atom.
Examples
Success:
      :- local variable(a,[]).
      :- local variable(count,0), variable(value,colour(red)).
Error:
      :- local variable(X, []).                      (Error 4).
      :- local variable(6, 0).                       (Error 5).
See Also
current_array / 2, array / 1, array / 2, decval / 1, incval / 1, bag_create / 1, getval / 2, setval / 2, reference / 1, reference / 2, variable / 1