Qualifications for foreign earned income exclusion

rules.pl

% Requirements, using Prolog syntax, to qualify for the foreign earned income exclusion
% See http://www.irs.gov/Individuals/International-Taxpayers/Foreign-Earned-Income-Exclusion

% facts which act as parameters to the loophole solver
:- dynamic
    us_citizen/0,
    us_resident_alien/0.

% See http://www.irs.gov/Individuals/International-Taxpayers/Foreign-Earned-Income-Exclusion-Can-I-Claim-the-Exclusion-or-Deduction
qualify :-
    foreign_earned_income,
    foreign_tax_home,
    ( us_citizen ->
        question_4
    ; us_resident_alien, home_country_has_tax_treaty ->
        question_4
    ; otherwise ->
        question_5
    ).

question_4 :-
    bona_fide_resident,
    residence_for_entire_tax_year,
    !.
question_4 :-
    question_5.
    
question_5 :-
    foreign_physical_presence(Days),
    Days >= 330.


% See http://www.irs.gov/Individuals/International-Taxpayers/Foreign-Earned-Income-Exclusion---What-is-Foreign-Earned-Income    
foreign_earned_income :-
    todo.


% See http://www.irs.gov/Individuals/International-Taxpayers/Foreign-Earned-Income-Exclusion---Tax-Home-in-Foreign-Country
foreign_tax_home :-
    todo.


% See http://www.irs.gov/Individuals/International-Taxpayers/Foreign-Earned-Income-Exclusion---Bona-Fide-Residence-Test
bona_fide_resident :-
    todo.


residence_for_entire_tax_year :-
    foreign_physical_presence(Days),
    Days >= 365.


% See http://www.irs.gov/Individuals/International-Taxpayers/Foreign-Earned-Income-Exclusion---Physical-Presence-Test
foreign_physical_presence(_Days) :-
    todo.