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16.11 Explaing the guile-log dynamic functions

Dynamic functions in guile-log prolog follows the iso prolog interface. But they are more powerful. They belong to a class of object that we can call dynamic objects for which dynamic features can be added how to backtrack store and restore state. The driving feature is that the state infromation is updated in a funcitonal manner and that its encapsulated with a thread safe handle. But the datastructure are not only functional, in order to have decent properties in prolog program and let them for example back track with the logic program we allow a mark and reset feature. To understand this scope please read about dynamic features. The dynamic functions are optimized for fast lookup and guile log prolog is fully indexed and can yield the matching items faster than it takes to actually perform any common match consequent. The target is for systems that update seldom and do lookup often. The dynamic functions assert* compainion will compile the program to bytecode/native for faster execution. Do not use dynamic functions as a hash table that updates often, for that use the hash table library. Also currently at most 10000 elements can be stored for a dynamic function. (The algorithm scales badly after that and we do not support larger than that).