Minerva supports so called term vectors to store and retrieve terms.

There exist different types of predicate classes to support the management of global data: the Minerva database (manipulated with assert, retract, clause, etc), global variables (manipulated with set_global, get_global, etc), blackboards (manipulated with bb_put, bb_get, etc) and term vectors.
There exist the following predicates to handle term vectors:

• tv_create/1
• tv_add/2
• tv_size/2
• tv_setsize/2
• tv_set/3
• tv_get/3
• tv_list/2

A term vector is a kind of dynamically resizable array of terms.
Before you can store/retrieve terms from a term vector, you have to create a term vector. This is done with tv_create/1. The term vector is initially empty, i.e. it's size is 0. You may add terms to the term vector with the predicates tv_add/2 or tv_set/3. You may retrieve all terms of the vector by calling tv_list/2 and you can access a single term with tv_get/3.

Examples:

main(_) :-
    my_findall(I, for(1,I,10), Numbers).

my_findall(Term, Goal, Terms) :-
    % create a term vector ...
    tv_create(Vector),
    % .. . add a bulk of data to it ...
    retrieve_info(Vector, Term, Goal),
    % ... and collect all terms.
    tv_list(Vector, Terms).

retrieve_info(Vector, Term, Goal) :-
    % call a goal ...
    call(Goal),
    % ... store the information ...
    tv_add(Vector, Term),
    % ... and backtrack until there are no more results.
    fail.
retrieve_info(_, _, _).

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