:- use_module(library(func)).
:- use_module(library(tap)).

two :-
    F = succ of plus(2),
    call(F, 4, Y),
    Y = 7.

multiple :-
    call(succ of succ of succ, 0, 3).

idempotent :-
    F = plus(3) of plus(1),
    G = plus(3) of plus(1),
    G = F,
    call(F, 1, X),
    call(G, 1, X).

evaluable_functions :-
    Plus3 = succ of _+1 of plus(1),
    call(Plus3, 0, 3).

'silly atom_codes' :-
    AtomCodes = string_codes of atom_string,
    call(AtomCodes, hi, [0'h, 0'i]).

dicts :-
    Lookup = greek{a: alpha, b: beta} of roman{1: a, 2: b},
    call(Lookup, 1, alpha),
    call(Lookup, 2, beta),
    \+ call(Lookup, 3, _).