%---------------------------------------------------------------------------%
% vim: ft=mercury ts=4 sw=4 et wm=0 tw=0
%---------------------------------------------------------------------------%
%
% This program causes the compiler (rotd-2016-06-09) to abort with the
% following:
%
% Uncaught Mercury exception:
% Software Error: map.lookup: key not found
%  Key Type: int
%  Key Value: 1
%  Value Type: hlds.hlds_pred.proc_info
%
%---------------------------------------------------------------------------%


:- module bug410.
:- interface.

:- import_module io.

:- pred main(io::di, io::uo) is det.

%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%

:- implementation.

:- import_module bool.
:- import_module char.
:- import_module int.
:- import_module list.
:- import_module maybe.
:- import_module random.
:- import_module solutions.
:- import_module string.
:- import_module time.

%---------------------------------------------------------------------------%

main(!IO) :-
    clock(Time, !IO),
    random.init(Time, RNG0),
    FormIGen = form1_gen(0, 0, [], []),
    Gens = [FormIGen],
    list.length(Gens, NumGens),
    make_titles(NumGens, Gens, 30, [], _, RNG0, _, !IO).

%---------------------------------------------------------------------------%

:- type generator == pred(maybe(string), list(string), list(string), random.supply, random.supply).
:- inst generator == (pred(out, in, out, in, out) is det).

    % There's a closing parenthesis missing here ---------------+
    %                                                           |
:- pred make_titles(int::in, list(generator)::in(list(generator), int::in,
    list(string)::in, list(string)::out, random.supply::in, random.supply::out,
    io::di, io::uo) is det.

make_titles(NumGens, GenPreds, N, !Used, !RNG, !IO) :-
    ( if N < 0 then
        true
    else
        random.random(1, NumGens, NumGen, !RNG),
        list.det_index1(GenPreds, NumGen, GenPred),
        GenPred(MaybeTitle, !Used, !RNG),
        (
            MaybeTitle = yes(Title),
            io.print_line(Title, !IO),
            make_titles(NumGens, GenPreds, N - 1, !Used, !RNG, !IO)
        ;
            MaybeTitle = no,
            make_titles(NumGens, GenPreds, N, !Used, !RNG, !IO)
        )
    ).

:- pred form1_gen(int::in, int::in, list(string)::in, list(string)::in,
    maybe(string)::out, list(string)::in, list(string)::out,
    random.supply::in, random.supply::out) is det.

form1_gen(_, _, _, _, MaybeTitle, !Used, !RNG) :-
    MaybeTitle = yes("foo").

%---------------------------------------------------------------------------%
:- end_module bug410.
%---------------------------------------------------------------------------%