Prolog: Convert list into dictionary?-CodePudding

I am searching some swi-prolog predicate:

list_to_dict(List, Dict) :- ??

Which is able to convert a list like

l = [a, b, c, d]

into a Prolog dict d whose keys are equal to the list indexes starting at 1. In this example above d is of form:

d = dict_label{1:a,2:b,3:c,4:d}

I would appreciate, if you can help me to find some general and hopefully short solution of that problem.

CodePudding user response：

You can use the following predicate:

% list_to_dict( Values,  Tag, -Dict)

  list_to_dict(Values, Tag, Dict) :-
      findall(Key-Value, nth1(Key, Values, Value), Pairs),
      dict_create(Dict, Tag, Pairs).

Example:

?- list_to_dict([a,b,c,d], dict_label, Dict).
Dict = dict_label{1:a, 2:b, 3:c, 4:d}.