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suspension_to_goal(+Susp, -Goal, -Module)
Succeeds for an unwoken suspension and returns the corresponding Goal
structure and context module.
- Susp
- A suspension.
- Goal
- A variable or a callable term.
- Module
- A variable or a module.
This built-in predicate is obsolete!
Description
   This built-in is used to access the contents of the abstract suspension
   data type.  It is complementary to make_suspension/3 as it returns the
   original goal structure and the module where make_suspension/3 was
   executed.  If applied to an already woken suspension it fails.
   Note that a suspension is not a standard Prolog data structure and can
   only be manipulated in a restricted way.  In particular, a suspension
   is not a term an atom of the form 'SUSP-...', although it is printed
   this way by default.  suspension_to_goal/3 is the only way to access the
   contents of a suspension.
Modes and Determinism
- suspension_to_goal(+, -, -) is semidet
Fail Conditions
Fails if the suspension is already dead
Exceptions
- (4) instantiation fault 
- Susp is not instantiated.
- (5) type error 
- Susp is not a suspension.
- (5) type error 
- Goal is neither variable nor a callable term.
- (5) type error 
- Module is neither variable nor atom.
Examples
[eclipse 1]: make_suspension(writeln(hello), 0, S),
        suspension_to_goal(S, Goal, Module).
S = 'SUSP-_303-susp'
Goal = writeln(hello)
Module = eclipse
Delayed goals:
        writeln(hello)
yes.
[eclipse 2]: make_suspension(writeln(hello), 0, S),
        call_suspension(S),
        suspension_to_goal(S, Goal, Module).
hello
no (more) solution.
See Also
get_suspension_data / 3, delayed_goals / 1, kill_suspension / 1, make_suspension / 3