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insert_suspension(?Term, +Susp, +Index, +Module)
Insert the suspension Susp into the Index'th suspension list of the
attribute Module for all attributed variables that occur in Term.
- Term
- Any Prolog term.
- Susp
- A suspension.
- Index
- An integer.
- Module
- An atom.
Description
   This predicate is used to insert a suspension into a suspension list in
   an attribute of one or more attributed variables.  Since Prolog does not allow to
   insert new elements into a list in constant time, ECLiPSe provides this
   predicate.  It finds all attributed variables occurring in the term Term and for
   each of them, it locates the attribute with the name Module.  This
   attribute must be a structure, otherwise an error is raised, which means
   that the attribute has to be initialised before calling
   insert_suspension/3.  The Index'th argument of the attribute structure
   is interpreted as a suspension list and the suspension Susp is inserted
   at the beginning of this list.  
Modes and Determinism
- insert_suspension(?, +, +, +) is det
Exceptions
- (4) instantiation fault 
- Susp or Index is not instantiated.
- (5) type error 
- Susp is not a suspension.
- (5) type error 
- Index is not an integer.
- (6) out of range 
- The attribute of a variable in Term is a structure whose arity is less than Index.
- (270) undefined variable attribute 
- The current module has no declared variable attribute.
- (271) bad format of the variable attribute 
- The attribute of a variable in Term is uninstantiated or it is not a structure.
- (271) bad format of the variable attribute 
- The suspension list in the attribute of a variable in Term is neither a list nor a free variable, or it contains an element which is not a suspension.
Examples
[eclipse 1]: meta_attribute(myatt,[]).
Yes (0.01s cpu)
[eclipse 2]: Att = att(_, hello), init_suspension_list(1, Att),
        add_attribute(X, Att, myatt), make_suspension(true, 1, S),
	insert_suspension(X, S, 1, myatt).
Att = att(['SUSP-_309-susp'], hello)
X = X
S = 'SUSP-_309-susp'
Delayed goals:
        true
Yes (0.00s cpu)
See Also
insert_suspension / 3, make_suspension / 3, meta_attribute / 2, enter_suspension_list / 3