chapter-5.erl

-module('chapter-5').
-export([map_search_pred/2]).

% write a funciton map_search(Map, Pred) that returns the first element {Key, Value}
% in the map for which Pred(Key, Value) is true.
% 16> A = fun(X, Y) -> case X > Y of true -> true; _ -> false end end. 
% #Fun<erl_eval.13.126501267>
% 17> A(1, 2).
% false
% 18> 'chapter-5':map_search_pred(#{1=>2, 4=>3}, A).
% {4,3}
% 19> 

map_search_pred(Map, Pred) ->
    map_search(maps:to_list(Map), Pred).

map_search([], _Pred) ->
    [];
map_search([H|T], Pred) ->
    {Key, Value} = H,
    case Pred(Key, Value) of
        true -> {Key, Value};
        _ -> map_search(T, Pred)
    end.