%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1999-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%

%%
-module(guard_SUITE).

-export([all/1,init_per_testcase/2,fin_per_testcase/2,init_all/1,finish_all/1,
	 bad_arith/1,bad_tuple/1,test_heap_guards/1,guard_bifs/1,
	 type_tests/1,const_guard/1,
	 const_cond/1,basic_not/1,complex_not/1,
	 semicolon/1,complex_semicolon/1,comma/1,
	 or_guard/1,more_or_guards/1,
	 complex_or_guards/1,and_guard/1,
	 xor_guard/1,more_xor_guards/1,
	 old_guard_tests/1,
	 build_in_guard/1,gbif/1,
	 t_is_boolean/1,is_function_2/1,
	 tricky/1,rel_ops/1,
	 basic_andalso_orelse/1,traverse_dcd/1,
	 check_qlc_hrl/1]).

-include("test_server.hrl").

-export([init/4]).
-import(lists, [member/2]).

all(suite) ->
    [{conf,init_all,cases(),finish_all}].

cases() ->
    [bad_arith,bad_tuple,test_heap_guards,guard_bifs,type_tests,const_guard,
     const_cond,basic_not,complex_not,
     semicolon,complex_semicolon,
     comma,or_guard,more_or_guards,
     complex_or_guards,and_guard,
     xor_guard,more_xor_guards,
     build_in_guard,old_guard_tests,gbif,
     t_is_boolean,is_function_2,tricky,rel_ops,
     basic_andalso_orelse,traverse_dcd,check_qlc_hrl].

init_per_testcase(_Case, Config) ->
    test_lib:interpret(?MODULE),
    ?line Dog = test_server:timetrap(?t:minutes(1)),
    [{watchdog,Dog}|Config].

fin_per_testcase(_Case, Config) ->
    Dog = ?config(watchdog, Config),
    ?t:timetrap_cancel(Dog),
    ok.

init_all(Config) when is_list(Config) ->
    ?line test_lib:interpret(?MODULE),
    ?line true = lists:member(?MODULE, int:interpreted()),
    ok.

finish_all(Config) when is_list(Config) ->
    ok.

bad_arith(doc) -> "Test that a bad arithmetic operation in a guard works correctly.";
bad_arith(suite) -> [];
bad_arith(Config) when list(Config) ->
    ?line 5 = bad_arith1(2, 3),
    ?line 10 = bad_arith1(1, infinity),
    ?line 10 = bad_arith1(infinity, 1),
    ?line 42 = bad_div(24, 0),
    ok.

bad_arith1(T1, T2) when T1+T2 < 10 ->
    T1+T2;
bad_arith1(_, _) ->
    10.

bad_div(A, B) when A/B > 0 ->
    A/B;
bad_div(A, B) when A div B > 0 ->
    A div B;
bad_div(_A, _B) ->
    42.

bad_tuple(doc) -> "Test that bad arguments to element/2 are handled correctly.";
bad_tuple(suite) -> [];
bad_tuple(Config) when list(Config) ->
    ?line error = bad_tuple1(a),
    ?line error = bad_tuple1({a, b}),
    ?line x = bad_tuple1({x, b}),
    ?line y = bad_tuple1({a, b, y}),
    ok.

bad_tuple1(T) when element(1, T) == x -> x;
bad_tuple1(T) when element(3, T) == y -> y;
bad_tuple1(_) -> error.

test_heap_guards(doc) -> "";
test_heap_guards(suite) -> [];
test_heap_guards(Config) when list(Config) ->
    ?line process_flag(trap_exit, true),
    ?line Tuple = {a, tuple, is, built, here, xxx},
    ?line List = [a, list, is, built, here],

    ?line try_fun(fun a_case/1, [Tuple], [Tuple]),
    ?line try_fun(fun a_case/1, [List], [List, List]),
    ?line try_fun(fun a_case/1, [a], [a]),

    ?line try_fun(fun an_if/1, [Tuple], [Tuple]),
    ?line try_fun(fun an_if/1, [List], [List, List]),
    ?line try_fun(fun an_if/1, [a], [a]),

    ?line try_fun(fun receive_test/1, [Tuple], [Tuple]),
    ?line try_fun(fun receive_test/1, [List], [List, List]),
    ?line try_fun(fun receive_test/1, [a], [a]),
    ok.

a_case(V) ->
    case V of
	T when T == {a, tuple, is, built, here, xxx} ->
	    [T];
	L when L == [a, list, is, built, here] ->
	    [L, L];
	a ->
	    [a]
    end.

an_if(V) ->
    if
	V == {a, tuple, is, built, here, xxx} ->
	    [V];
	V == [a, list, is, built, here] ->
	    [V, V];
	V == a ->
	    [a]
    end.

receive_test(V) ->
    self() ! V,
    a_receive().

a_receive() ->
    receive
	T when T == {a, tuple, is, built, here, xxx} ->
	    [T];
	L when L == [a, list, is, built, here] ->
	    [L, L];
	a ->
	    [a]
    end.

try_fun(Fun, Args, Result) ->
    try_fun(16, Fun, Args, Result, []).

try_fun(0, _, _, _, _) ->
    ok;
try_fun(Iter, Fun, Args, Result, Filler) ->
    Pid = spawn_link(?MODULE, init, [self(),Fun,Args,list_to_tuple(Filler)]),
    receive
	{'EXIT',Pid,{result,Result}} ->
	    ?line try_fun(Iter-1, Fun, Args, Result, [0|Filler]);
	{'EXIT',Pid,{result,Other}} ->
	    ?line io:format("Expected ~p; got ~p~n", [Result,Other]),
	    ?line test_server:fail();
	Other ->
	    ?line test_server:fail({unexpected_message,Other})
    end.

init(_ReplyTo, Fun, Args, Filler) ->
    Result = {result, apply(Fun, Args)},
    dummy(Filler),
    io:format("~p: result = ~p\n", [?LINE,Result]),
    exit(Result).

dummy(_) ->
    ok.

guard_bifs(doc) -> "Test all guard bifs with nasty (but legal arguments).";
guard_bifs(suite) -> [];
guard_bifs(Config) when list(Config) ->
    ?line Big = -237849247829874297658726487367328971246284736473821617265433,
    ?line Float = 387924.874,

    %% Succeding use of guard bifs.

    ?line try_gbif('abs/1', Big, -Big),
    ?line try_gbif('float/1', Big, float(Big)),
    ?line try_gbif('trunc/1', Float, 387924.0),
    ?line try_gbif('round/1', Float, 387925.0),
    ?line try_gbif('length/1', [], 0),

    ?line try_gbif('length/1', [a], 1),
    ?line try_gbif('length/1', [a, b], 2),
    ?line try_gbif('length/1', lists:seq(0, 31), 32),

    ?line try_gbif('hd/1', [a], a),
    ?line try_gbif('hd/1', [a, b], a),

    ?line try_gbif('tl/1', [a], []),
    ?line try_gbif('tl/1', [a, b], [b]),
    ?line try_gbif('tl/1', [a, b, c], [b, c]),

    ?line try_gbif('size/1', {}, 0),
    ?line try_gbif('size/1', {a}, 1),
    ?line try_gbif('size/1', {a, b}, 2),
    ?line try_gbif('size/1', {a, b, c}, 3),
    ?line try_gbif('size/1', list_to_binary([]), 0),
    ?line try_gbif('size/1', list_to_binary([1]), 1),
    ?line try_gbif('size/1', list_to_binary([1, 2]), 2),
    ?line try_gbif('size/1', list_to_binary([1, 2, 3]), 3),

    ?line try_gbif('element/2', {x}, {1, x}),
    ?line try_gbif('element/2', {x, y}, {1, x}),
    ?line try_gbif('element/2', {x, y}, {2, y}),

    ?line try_gbif('self/0', 0, self()),
    ?line try_gbif('node/0', 0, node()),
    ?line try_gbif('node/1', self(), node()),

    %% Failing use of guard bifs.

    ?line try_fail_gbif('abs/1', Big, 1),
    ?line try_fail_gbif('abs/1', [], 1),

    ?line try_fail_gbif('float/1', Big, 42),
    ?line try_fail_gbif('float/1', [], 42),

    ?line try_fail_gbif('trunc/1', Float, 0.0),
    ?line try_fail_gbif('trunc/1', [], 0.0),

    ?line try_fail_gbif('round/1', Float, 1.0),
    ?line try_fail_gbif('round/1', [], a),

    ?line try_fail_gbif('length/1', [], 1),
    ?line try_fail_gbif('length/1', [a], 0),
    ?line try_fail_gbif('length/1', a, 0),
    ?line try_fail_gbif('length/1', {a}, 0),

    ?line try_fail_gbif('hd/1', [], 0),
    ?line try_fail_gbif('hd/1', [a], x),
    ?line try_fail_gbif('hd/1', x, x),

    ?line try_fail_gbif('tl/1', [], 0),
    ?line try_fail_gbif('tl/1', [a], x),
    ?line try_fail_gbif('tl/1', x, x),

    ?line try_fail_gbif('size/1', {}, 1),
    ?line try_fail_gbif('size/1', [], 0),
    ?line try_fail_gbif('size/1', [a], 1),

    ?line try_fail_gbif('element/2', {}, {1, x}),
    ?line try_fail_gbif('element/2', {x}, {1, y}),
    ?line try_fail_gbif('element/2', [], {1, z}),

    ?line try_fail_gbif('self/0', 0, list_to_pid("<0.0.0>")),
    ?line try_fail_gbif('node/0', 0, xxxx),
    ?line try_fail_gbif('node/1', self(), xxx),
    ?line try_fail_gbif('node/1', yyy, xxx),
    ok.

try_gbif(Id, X, Y) ->
    case guard_bif(Id, X, Y) of
	{Id, X, Y} ->
	    io:format("guard_bif(~p, ~p, ~p) -- ok", [Id, X, Y]);
	Other ->
	    ?line ok = io:format("guard_bif(~p, ~p, ~p) -- bad result: ~p\n",
				 [Id, X, Y, Other]),
	    ?line test_server:fail()
    end.

try_fail_gbif(Id, X, Y) ->
    case catch guard_bif(Id, X, Y) of
	{'EXIT', {function_clause,{?MODULE,guard_bif,[Id,X,Y]}}} -> %Jam
	    io:format("guard_bif(~p, ~p, ~p) -- ok", [Id,X,Y]);
	{'EXIT', {function_clause,[{?MODULE,guard_bif,[Id,X,Y]}|_]}} ->	%Beam
	    io:format("guard_bif(~p, ~p, ~p) -- ok", [Id,X,Y]);
	Other ->
	    ?line ok = io:format("guard_bif(~p, ~p, ~p) -- bad result: ~p\n",
				 [Id, X, Y, Other]),
	    ?line test_server:fail()
    end.

guard_bif('abs/1', X, Y) when abs(X) == Y ->
    {'abs/1', X, Y};
guard_bif('float/1', X, Y) when float(X) == Y ->
    {'float/1', X, Y};
guard_bif('trunc/1', X, Y) when trunc(X) == Y ->
    {'trunc/1', X, Y};
guard_bif('round/1', X, Y) when round(X) == Y ->
    {'round/1', X, Y};
guard_bif('length/1', X, Y) when length(X) == Y ->
    {'length/1', X, Y};
guard_bif('hd/1', X, Y) when hd(X) == Y ->
    {'hd/1', X, Y};
guard_bif('tl/1', X, Y) when tl(X) == Y ->
    {'tl/1', X, Y};
guard_bif('size/1', X, Y) when size(X) == Y ->
    {'size/1', X, Y};
guard_bif('element/2', X, {Pos, Expected}) when element(Pos, X) == Expected ->
    {'element/2', X, {Pos, Expected}};
guard_bif('self/0', X, Y) when self() == Y ->
    {'self/0', X, Y};
guard_bif('node/0', X, Y) when node() == Y ->
    {'node/0', X, Y};
guard_bif('node/1', X, Y) when node(X) == Y ->
    {'node/1', X, Y}.

type_tests(doc) -> "Test the type tests.";
type_tests(suite) -> [];
type_tests(Config) when list(Config) ->
    ?line Types = all_types(),
    ?line Tests = type_test_desc(),
    ?line put(errors, 0),
    ?line put(violations, 0),
    ?line type_tests(Tests, Types),
    ?line case {get(errors), get(violations)} of
	      {0, 0} ->
		  ok;
	      {0, N} ->
		  {comment, integer_to_list(N) ++ " standard violation(s)"};
	      {Errors, Violations} ->
		  io:format("~p sub test(s) failed, ~p violation(s)",
			    [Errors, Violations]),
		  ?line test_server:fail()
	  end.

type_tests([{Test, AllowedTypes}| T], AllTypes) ->
    type_tests(Test, AllTypes, AllowedTypes),
    type_tests(T, AllTypes);
type_tests([], _) ->
    ok.

type_tests(Test, [Type|T], Allowed) ->
    {TypeTag, Value} = Type,
    case member(TypeTag, Allowed) of
	true ->
	    case catch type_test(Test, Value) of
		Test ->
		    ok;
		_Other ->
		    io:format("Test ~p(~p) failed", [Test, Value]),
		    put(errors, get(errors) + 1)
	    end;
	false ->
	    case catch type_test(Test, Value) of
		{'EXIT', {function_clause, {?MODULE, type_test, [Test, Value]}}} ->
		    ok;
		{'EXIT', {function_clause,[{?MODULE,type_test,[Test,Value]}|_]}} ->
		    ok;
		{'EXIT',Other} ->
		    ?line test_server:fail({unexpected_error_reason,Other});
		tuple when function(Value) ->
		    io:format("Standard violation: Test ~p(~p) should fail",
			      [Test, Value]),
		    put(violations, get(violations) + 1);
		_Other ->
		    io:format("Test ~p(~p) succeeded (should fail)", [Test, Value]),
		    put(errors, get(errors) + 1)
	    end
    end,
    type_tests(Test, T, Allowed);
type_tests(_, [], _) ->
    ok.

all_types() ->
    [{small, 42},
     {big, 392742928742947293873938792874019287447829874290742},
     {float, 3.14156},
     {nil, []},
     {cons, [a]},
     {tuple, {a, b}},
     {atom, xxxx},
     {ref, make_ref()},
     {pid, self()},
     {port, open_port({spawn, efile}, [])},
     {function, fun(X) -> X+1, "" end},
     {binary, list_to_binary([])}].

type_test_desc() ->
    [{integer, [small, big]},
     {float, [float]},
     {number, [small, big, float]},
     {atom, [atom]},
     {list, [cons, nil]},
     {nonempty_list, [cons]},
     {nil, [nil]},
     {tuple, [tuple]},
     {pid, [pid]},
     {port, [port]},
     {reference, [ref]},
     {function, [function]}].

type_test(integer, X) when integer(X) ->
    integer;
type_test(float, X) when float(X) ->
    float;
type_test(number, X) when number(X) ->
    number;
type_test(atom, X) when atom(X) ->
    atom;
type_test(list, X) when list(X) ->
    list;
type_test(nonempty_list, [_]) ->
    nonempty_list;
type_test(nil, []) ->
    nil;
type_test(tuple, X) when tuple(X) ->
    tuple;
type_test(pid, X) when pid(X) ->
    pid;
type_test(reference, X) when reference(X) ->
    reference;
type_test(port, X) when port(X) ->
    port;
type_test(binary, X) when binary(X) ->
    binary;
type_test(function, X) when function(X) ->
    function.

const_guard(Config) when is_list(Config) ->
    ?line if
	      (0 == 0) and ((0 == 0) or (0 == 0)) ->
		  ok
	  end.


const_cond(Config) when is_list(Config) ->
    ?line ok = const_cond({}, 0),
    ?line ok = const_cond({a}, 1),
    ?line error = const_cond({a,b}, 3),
    ?line error = const_cond({a}, 0),
    ?line error = const_cond({a,b}, 1),
    ok.

const_cond(T, Sz) ->
    case T of
	_X when false -> never;
	_X when tuple(T), eq == eq, size(T) == Sz -> ok;
	_X when tuple(T), eq == leq, size(T) =< Sz -> ok;
	_X -> error
    end.

basic_not(Config) when is_list(Config) ->
    True = id(true),
    False = id(false),
    Glurf = id(glurf),
    A = id(5),
    B = id(37.5),
    C = id(-1),
    D = id(5),
    ATuple = {False,True,Glurf},

    ?line check(fun() -> if not false -> ok; true -> error end end, ok),
    ?line check(fun() -> if not true -> ok; true -> error end end, error),
    ?line check(fun() -> if not False -> ok; true -> error end end, ok),
    ?line check(fun() -> if not True -> ok; true -> error end end, error),

    ?line check(fun() -> if A > B -> gt; A < B -> lt; A == B -> eq end end, lt),
    ?line check(fun() -> if A > C -> gt; A < C -> lt; A == C -> eq end end, gt),
    ?line check(fun() -> if A > D -> gt; A < D -> lt; A == D -> eq end end, eq),

    ?line check(fun() -> if not (7 > 453) -> le; not (7 < 453) -> ge;
			    not (7 == 453) -> ne; true -> eq end end, le),
    ?line check(fun() -> if not (7 > -8) -> le; not (7 < -8) -> ge;
			    not (7 == -8) -> ne; true -> eq end end, ge),
    ?line check(fun() -> if not (7 > 7) -> le; not (7 < 7) -> ge;
			    not (7 == 7) -> ne; true -> eq end end, le),

    ?line check(fun() -> if not (A > B) -> le; not (A < B) -> ge;
			    not (A == B) -> ne; true -> eq end end, le),
    ?line check(fun() -> if not (A > C) -> le; not (A < C) -> ge;
			    not (A == C) -> ne; true -> eq end end, ge),
    ?line check(fun() -> if not (A > D) -> le; not (A < D) -> ge;
			    not (A == D) -> ne; true -> eq end end, le),

    ?line check(fun() -> if not element(1, ATuple) -> ok; true -> error end end, ok),
    ?line check(fun() -> if not element(2, ATuple) -> ok; true -> error end end, error),
    ?line check(fun() -> if not element(3, ATuple) -> ok; true -> error end end, error),

    ?line check(fun() -> if not glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if not Glurf -> ok; true -> error end end, error),

    ok.

complex_not(Config) when is_list(Config) ->
    ATuple = id({false,true,gurka}),
    ?line check(fun() -> if not(element(1, ATuple)) -> ok; true -> error end end, ok),
    ?line check(fun() -> if not(element(2, ATuple)) -> ok; true -> error end end, error),

    ?line check(fun() -> if not(element(3, ATuple) == gurka) -> ok;
			    true -> error end end, error),
    ?line check(fun() -> if not(element(3, ATuple) =/= gurka) -> ok;
			    true -> error end end, ok),

    ?line check(fun() -> if {a,not(element(2, ATuple))} == {a,false} -> ok;
			    true -> error end end, ok),
    ?line check(fun() -> if {a,not(element(1, ATuple))} == {a,false} -> ok;
			    true -> error end end, error),

    ?line check(fun() -> if not(element(1, ATuple) or element(3, ATuple)) -> ok;
			    true -> error end end, error),

    %% orelse
    ?line check(fun() -> if not(element(1, ATuple) orelse element(3, ATuple)) -> ok;
			    true -> error end end, error),

    ok.

semicolon(Config) when is_list(Config) ->

    %% True/false combined using ';' (literal atoms).

    ?line check(fun() -> if true; false -> ok end end, ok),
    ?line check(fun() -> if false; true -> ok end end, ok),
    ?line check(fun() -> if true; true -> ok end end, ok),
    ?line check(fun() -> if false; false -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if false; false -> ok end),
			exit
		end, exit),

    %% True/false combined used ';'.

    True = id(true),
    False = id(false),

    ?line check(fun() -> if True; False -> ok end end, ok),
    ?line check(fun() -> if False; True -> ok end end, ok),
    ?line check(fun() -> if True; True -> ok end end, ok),
    ?line check(fun() -> if False; False -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if False; False -> ok end),
			exit
		end, exit),

    %% Combine true/false with a non-boolean value.
    Glurf = id(glurf),


    ?line check(fun() -> if True; Glurf -> ok end end, ok),
    ?line check(fun() -> if Glurf; True -> ok end end, ok),
    ?line check(fun() -> if Glurf; Glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if False; Glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if Glurf; False -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if Glurf; Glurf -> ok end),
			exit
		end, exit),

    %% Combine true/false with errors.

    ATuple = id({false,true,gurka}),

    ?line check(fun() -> if True; element(42, ATuple) -> ok end end, ok),
    ?line check(fun() -> if element(42, ATuple); True -> ok end end, ok),
    ?line check(fun() -> if element(42, ATuple); element(42, ATuple) -> ok;
			    true -> error end end, error),
    ?line check(fun() -> if False; element(42, ATuple) -> ok;
			    true -> error end end, error),
    ?line check(fun() -> if element(42, ATuple);
			    False -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if element(42, ATuple);
				      element(42, ATuple) -> ok end),
			exit
		end, exit),

    ok.

complex_semicolon(Config) when is_list(Config) ->
    ?line ok = csemi1(int, {blurf}),
    ?line ok = csemi1(string, {blurf}),
    ?line ok = csemi1(float, [a]),
    ?line error = csemi1(35, 42),

    %% 2
    ?line ok = csemi2({}, {a,b,c}),
    ?line ok = csemi2({1,3.5}, {a,b,c}),
    ?line ok = csemi2(dum, {a,b,c}),

    ?line ok = csemi2({45,-19.3}, {}),
    ?line ok = csemi2({45,-19.3}, {dum}),
    ?line ok = csemi2({45,-19.3}, {dum,dum}),

    ?line error = csemi2({45}, {dum}),
    ?line error = csemi2([], {dum}),
    ?line error = csemi2({dum}, []),
    ?line error = csemi2([], []),

    %% 3
    ?line csemi3(fun csemi3a/4),
    ?line csemi3(fun csemi3b/4),
    ?line csemi3(fun csemi3c/4),

    %% 4
    ?line csemi4(fun csemi4a/4),
    ?line csemi4(fun csemi4b/4),
    ?line csemi4(fun csemi4c/4),
    ?line csemi4(fun csemi4d/4),

    %% 4, 'orelse' instead of 'or'
    ?line csemi4_orelse(fun csemi4_orelse_a/4),
    ?line csemi4_orelse(fun csemi4_orelse_b/4),
    ?line csemi4_orelse(fun csemi4_orelse_c/4),
    ?line csemi4_orelse(fun csemi4_orelse_d/4),

    ok.

csemi1(Type, Val) when is_list(Val), Type == float;
		       Type == int; Type == string -> ok;
csemi1(_, _) -> error.

csemi2(A, B) when size(A) > 1; size(B) > 2 -> ok;
csemi2(_, _) -> error.

csemi3(Csemi3) ->
    ok = Csemi3({}, {a,b,c}, [0], [0]),
    ok = Csemi3({1,3.5}, {a,b,c}, -1, -1),
    ok = Csemi3(dum, {a,b,c}, 0.0, 0.0),
    ok = Csemi3(dum, {c}, b, a),
    ok = Csemi3(dum, <<1,2,3>>, 0.0, 0.0),
    ok = Csemi3(<<3.5/float>>, {a,b,c}, -1, -1),

    ok = Csemi3({45,-19.3}, {}, [], []),
    ok = Csemi3({45,-19.3}, {dum}, 42, 42),
    ok = Csemi3({45,-19.3}, {dum,dum}, 33, 33),

    ok = Csemi3({45}, {dum}, 1.0, 0),
    ok = Csemi3([a], {dum}, 1.0, 0),
    ok = Csemi3({dum}, [], 1.0, 0),
    ok = Csemi3([], [], 1.0, 0),
    ok = Csemi3(blurf, {dum}, 1.0, 0),
    ok = Csemi3({a}, blurf, 1.0, 0),
    ok = Csemi3([a], [dum], 1.0, 0),
    ok = Csemi3({dum}, [], 1.0, 0),
    ok = Csemi3([], [], 1.0, 0),

    error = Csemi3({45}, {dum}, 0, 0),
    error = Csemi3([a], {dum}, 0, 0),
    error = Csemi3({dum}, [], 0, 0),
    error = Csemi3([], [], 0, 0),
    ok.

csemi3a(A, B, X, Y) when X > Y; size(A) > 1; size(B) > 2 -> ok;
csemi3a(_, _, _, _) -> error.

csemi3b(A, B, X, Y) when size(A) > 1; X > Y; size(B) > 2 -> ok;
csemi3b(_, _, _, _) -> error.

csemi3c(A, B, X, Y) when size(A) > 1; size(B) > 2; X > Y -> ok;
csemi3c(_, _, _, _) -> error.


csemi4(Test) ->
    ok = Test({a,b}, 2, {c,d}, 2),
    ok = Test({1,2,3}, 0, [], 0),
    ok = Test({}, 2, blurf, 0),
    ok = Test({}, 2, {1}, 2),

    error = Test([], 4, {}, 0),
    error = Test({}, 0, [a,b], 4),
    error = Test({}, 0, [a,b], 0),
    error = Test([], 0, {}, 0),
    error = Test({}, 0, {}, 0),

    ok.

csemi4a(A, X, B, Y) when (size(A) > 1) or (X > 1);
			 (size(B) > 1) or (Y > 1) -> ok;
csemi4a(_, _, _, _) -> error.

csemi4b(A, X, B, Y) when (X > 1) or (size(A) > 1);
			 (size(B) > 1) or (Y > 1) -> ok;
csemi4b(_, _, _, _) -> error.

csemi4c(A, X, B, Y) when (size(A) > 1) or (X > 1);
			 (Y > 1) or (size(B) > 1) -> ok;
csemi4c(_, _, _, _) -> error.

csemi4d(A, X, B, Y) when (X > 1) or (size(A) > 1);
			 (Y > 1) or (size(B) > 1) -> ok;
csemi4d(_, _, _, _) -> error.


csemi4_orelse(Test) ->
    ok = Test({a,b}, 2, {c,d}, 2),
    ok = Test({1,2,3}, 0, [], 0),
    ok = Test({}, 2, blurf, 0),
    ok = Test({}, 2, {1}, 2),

    ?line error = Test([], 1, {}, 0),

    ok.

csemi4_orelse_a(A, X, B, Y) when (size(A) > 1) orelse (X > 1);
			 (size(B) > 1) orelse (Y > 1) -> ok;
csemi4_orelse_a(_, _, _, _) -> error.

csemi4_orelse_b(A, X, B, Y) when (X > 1) orelse (size(A) > 1);
			 (size(B) > 1) orelse (Y > 1) -> ok;
csemi4_orelse_b(_, _, _, _) -> error.

csemi4_orelse_c(A, X, B, Y) when (size(A) > 1) orelse (X > 1);
                           (Y > 1) orelse (size(B) > 1) -> ok;
csemi4_orelse_c(_, _, _, _) -> error.

csemi4_orelse_d(A, X, B, Y) when (X > 1) or (size(A) > 1);
			 (Y > 1) or (size(B) > 1) -> ok;
csemi4_orelse_d(_, _, _, _) -> error.


comma(Config) when is_list(Config) ->

    %% ',' combinations of literal true/false.

    ?line check(fun() -> if true, false -> ok; true -> error end end, error),
    ?line check(fun() -> if false, true -> ok; true -> error end end, error),
    ?line check(fun() -> if true, true -> ok end end, ok),
    ?line check(fun() -> if false, false -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if true, false -> ok;
				      false, true -> ok;
				      false, false -> ok
				   end),
			exit
		end, exit),

    %% ',' combinations of true/false in variables.

    True = id(true),
    False = id(false),

    ?line check(fun() -> if True, False -> ok; true -> error end end, error),
    ?line check(fun() -> if False, True -> ok; true -> error end end, error),
    ?line check(fun() -> if True, True -> ok end end, ok),
    ?line check(fun() -> if False, False -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if True, False -> ok;
				      False, True -> ok;
				      False, False -> ok
				   end),
			exit
		end, exit),

    %% ',' combinations of true/false, and non-boolean in variables.

    Glurf = id(glurf),

    ?line check(fun() -> if True, Glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if Glurf, True -> ok; true -> error end end, error),
    ?line check(fun() -> if True, True -> ok end end, ok),
    ?line check(fun() -> if Glurf, Glurf -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if True, Glurf -> ok;
				      Glurf, True -> ok;
				      Glurf, Glurf -> ok
				   end),
			exit
		end, exit),

    %% ',' combinations of true/false with errors.
    ATuple = id({a,b,c}),

    ?line check(fun() -> if True, element(42, ATuple) -> ok;
			    true -> error end end, error),
    ?line check(fun() -> if element(42, ATuple), True -> ok;
			    true -> error end end, error),
    ?line check(fun() -> if True, True -> ok end end, ok),
    ?line check(fun() -> if element(42, ATuple), element(42, ATuple) -> ok;
			    true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if True, element(42, ATuple) -> ok;
				      element(42, ATuple), True -> ok;
				      element(42, ATuple), element(42, ATuple) -> ok
				   end),
			exit
		end, exit),

    ok.

or_guard(Config) when is_list(Config) ->
    True = id(true),
    False = id(false),
    Glurf = id(glurf),

    %% 'or' combinations of literal true/false.
    ?line check(fun() -> if true or false -> ok end end, ok),
    ?line check(fun() -> if false or true -> ok end end, ok),
    ?line check(fun() -> if true or true -> ok end end, ok),
    ?line check(fun() -> if false or false -> ok; true -> error end end, error),

    ?line check(fun() -> if glurf or true -> ok; true -> error end end, error),
    ?line check(fun() -> if true or glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if glurf or glurf -> ok; true -> error end end, error),

    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if false or false -> ok end),
			exit
		end, exit),


    %% 'or' combinations using variables containing true/false.
    ?line check(fun() -> if True or False -> ok end end, ok),
    ?line check(fun() -> if False or True -> ok end end, ok),
    ?line check(fun() -> if True or True -> ok end end, ok),
    ?line check(fun() -> if False or False -> ok; true -> error end end, error),

    ?line check(fun() -> if True or Glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if Glurf or True -> ok; true -> error end end, error),
    ?line check(fun() -> if Glurf or Glurf -> ok; true -> error end end, error),

    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if False or False -> ok end),
			exit
		end, exit),

    ok.

more_or_guards(Config) when is_list(Config) ->
    True = id(true),
    False = id(false),
    ATuple = id({false,true,gurka}),

    ?line check(fun() ->
			if element(42, ATuple) or False -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if False or element(42, ATuple) -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if element(18, ATuple) or element(42, ATuple) -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if True or element(42, ATuple) -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if element(42, ATuple) or True -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if element(1, ATuple) or element(42, ATuple) or True -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if element(1, ATuple) or True or element(42, ATuple) -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if
			    (<<False:8>> == <<0>>) or element(2, ATuple) -> ok;
			    true -> error end
		end, error),

    ?line check(fun() ->
			if
			    element(2, ATuple) or (<<True:8>> == <<1>>) -> ok;
			    true -> error end
		end, error),

    ?line check(fun() ->
			if element(2, ATuple) or element(42, ATuple) -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if
			    element(1, ATuple) or
			    element(2, ATuple) or
			    element(19, ATuple) -> ok;
			    true -> error end
		end, error),
    ok.

complex_or_guards(Config) when is_list(Config) ->
    %% complex_or_1/2
    ?line ok = complex_or_1({a,b,c,d}, {1,2,3}),
    ?line ok = complex_or_1({a,b,c,d}, {1}),
    ?line ok = complex_or_1({a}, {1,2,3}),
    ?line error = complex_or_1({a}, {1}),

    ?line error = complex_or_1(1, 2),
    ?line error = complex_or_1([], {a,b,c,d}),
    ?line error = complex_or_1({a,b,c,d}, []),


    %% complex_or_2/1
    ?line ok = complex_or_2({true,{}}),
    ?line ok = complex_or_2({false,{a}}),
    ?line ok = complex_or_2({false,{a,b,c}}),
    ?line ok = complex_or_2({true,{a,b,c,d}}),

    ?line error = complex_or_2({blurf,{a,b,c}}),

    ?line error = complex_or_2({true}),
    ?line error = complex_or_2({true,no_tuple}),
    ?line error = complex_or_2({true,[]}),

    %% complex_or_3/2
    ?line ok = complex_or_3({true}, {}),
    ?line ok = complex_or_3({false}, {a}),
    ?line ok = complex_or_3({false}, {a,b,c}),
    ?line ok = complex_or_3({true}, {a,b,c,d}),
    ?line ok = complex_or_3({false}, <<1,2,3>>),
    ?line ok = complex_or_3({true}, <<1,2,3,4>>),

    ?line error = complex_or_3(blurf, {a,b,c}),

    ?line error = complex_or_3({false}, <<1,2,3,4>>),
    ?line error = complex_or_3([], <<1,2>>),
    ?line error = complex_or_3({true}, 45),
    ?line error = complex_or_3(<<>>, <<>>),

    %% complex_or_4/2
    ?line ok = complex_or_4(<<1,2,3>>, {true}),
    ?line ok = complex_or_4(<<1,2,3>>, {false}),
    ?line ok = complex_or_4(<<1,2,3>>, {true}),
    ?line ok = complex_or_4({1,2,3}, {true}),
    ?line error = complex_or_4({1,2,3,4}, {false}),

    ?line error = complex_or_4(<<1,2,3,4>>, []),
    ?line error = complex_or_4([], {true}),

    %% complex_or_5/2
    ?line ok = complex_or_5(<<1>>, {false}),
    ?line ok = complex_or_5(<<1,2,3>>, {true}),
    ?line ok = complex_or_5(<<1,2,3,4>>, {false}),
    ?line ok = complex_or_5({1,2,3}, {false}),
    ?line ok = complex_or_5({1,2,3,4}, {false}),

    ?line error = complex_or_5(blurf, {false}),
    ?line error = complex_or_5(<<1>>, klarf),
    ?line error = complex_or_5(blurf, klarf),

    %% complex_or_6/2
    ?line ok = complex_or_6({true,true}, {1,2,3,4}),
    ?line ok = complex_or_6({true,true}, <<1,2,3,4>>),
    ?line ok = complex_or_6({false,false}, <<1,2,3,4>>),
    ?line ok = complex_or_6({false,true}, <<1>>),
    ?line ok = complex_or_6({true,false}, {1}),
    ?line ok = complex_or_6({true,true}, {1}),

    ?line error = complex_or_6({false,false}, {1}),

    ?line error = complex_or_6({true}, {1,2,3,4}),
    ?line error = complex_or_6({}, {1,2,3,4}),
    ?line error = complex_or_6([], {1,2,3,4}),
    ?line error = complex_or_6([], {1,2,3,4}),
    ?line error = complex_or_6({true,false}, klurf),

    ok.

complex_or_1(A, B) ->
    if
	((3 < size(A)) and (size(A) < 9)) or
	((2 < size(B)) and (size(B) < 7)) -> ok;
	true -> error
    end.

complex_or_2(Tuple) ->
    if
	element(1, Tuple) or not (size(element(2, Tuple)) > 3) -> ok;
	true -> error
    end.

complex_or_3(A, B) ->
    if
	not (size(B) > 3) or element(1, A) -> ok;
	true -> error
    end.

complex_or_4(A, B) ->
    if
	not (is_tuple(A) and (size(A) > 3)) or element(1, B) -> ok;
	true -> error
    end.

complex_or_5(A, B) ->
    if
	not (is_tuple(A) or (size(A) > 3)) or not element(1, B) -> ok;
	true -> error
    end.

complex_or_6(A, B) ->
    if
	not (not element(1, A) and not element(2, A)) or
	not (not (size(B) > 3)) -> ok;
	true -> error
    end.

and_guard(Config) when is_list(Config) ->

    %% 'and' combinations of literal true/false.

    ?line check(fun() -> if true and false -> ok; true -> error end end, error),
    ?line check(fun() -> if false and true -> ok; true -> error end end, error),
    ?line check(fun() -> if true and true -> ok end end, ok),
    ?line check(fun() -> if false and false -> ok; true -> error end end, error),

    ?line check(fun() -> if glurf and true -> ok; true -> error end end, error),
    ?line check(fun() -> if true and glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if glurf and glurf -> ok; true -> error end end, error),

    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if true and false -> ok;
				      false and true -> ok;
				      false and false -> ok
				   end),
			exit
		end, exit),

    %% 'and' combinations of true/false in variables.

    True = id(true),
    False = id(false),

    ?line check(fun() -> if True and False -> ok; true -> error end end, error),
    ?line check(fun() -> if False and True -> ok; true -> error end end, error),
    ?line check(fun() -> if True and True -> ok end end, ok),
    ?line check(fun() -> if False and False -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if True and False -> ok;
				      False and True -> ok;
				      False and False -> ok
				   end),
			exit
		end, exit),

    %% 'and' combinations of true/false and a non-boolean in variables.

    Glurf = id(glurf),

    ?line check(fun() -> if True and Glurf -> ok; true -> error end end, error),
    ?line check(fun() -> if Glurf and True -> ok; true -> error end end, error),
    ?line check(fun() -> if True and True -> ok end end, ok),
    ?line check(fun() -> if Glurf and Glurf -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if True and Glurf -> ok;
				      Glurf and True -> ok;
				      Glurf and Glurf -> ok
				   end),
			exit
		end, exit),

    %% 'and' combinations of true/false with errors.
    ATuple = id({a,b,c}),

    ?line check(fun() -> if True and element(42, ATuple) -> ok;
			    true -> error end end, error),
    ?line check(fun() -> if element(42, ATuple) and True -> ok;
			    true -> error end end, error),
    ?line check(fun() -> if True and True -> ok end end, ok),
    ?line check(fun() -> if element(42, ATuple) and element(42, ATuple) -> ok;
			    true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} =
			    (catch if True and element(42, ATuple) -> ok;
				      element(42, ATuple) and True -> ok;
				      element(42, ATuple) and element(42, ATuple) -> ok
				   end),
			exit
		end, exit),

    ?line ok = relprod({'Set',a,b}, {'Set',a,b}),

    ok.

relprod(R1, R2) when (erlang:size(R1) =:= 3) and (erlang:element(1,R1) =:= 'Set'), (erlang:size(R2) =:= 3) and (erlang:element(1,R2) =:= 'Set') ->
    ok.


xor_guard(Config) when is_list(Config) ->

    %% 'xor' combinations of literal true/false.
    ?line check(fun() -> if true xor false -> ok end end, ok),
    ?line check(fun() -> if false xor true -> ok end end, ok),
    ?line check(fun() -> if true xor true -> ok; true -> error end end, error),
    ?line check(fun() -> if false xor false -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if false xor false -> ok end),
			exit
		end, exit),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if true xor true -> ok end),
			exit
		end, exit),


    %% 'xor' combinations using variables containing true/false.

    True = id(true),
    False = id(false),

    ?line check(fun() -> if True xor False -> ok end end, ok),
    ?line check(fun() -> if False xor True -> ok end end, ok),
    ?line check(fun() -> if True xor True -> ok; true -> error end end, error),
    ?line check(fun() -> if False xor False -> ok; true -> error end end, error),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if False xor False -> ok end),
			exit
		end, exit),
    ?line check(fun() ->
			{'EXIT',{if_clause,_}} = (catch if True xor True -> ok end),
			exit
		end, exit),

    ok.

more_xor_guards(Config) when is_list(Config) ->
    True = id(true),
    False = id(false),
    ATuple = id({false,true,gurka}),

    ?line check(fun() ->
			if element(42, ATuple) xor False -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if False xor element(42, ATuple) xor False -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if element(18, ATuple) xor element(42, ATuple) -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if True xor element(42, ATuple) -> ok;
			   true -> error end
		end, error),

    ?line check(fun() ->
			if element(42, ATuple) xor True -> ok;
			   true -> error end
		end, error),
    ok.

build_in_guard(Config) when is_list(Config) ->
    SubBin = <<5.0/float>>,
    ?line B = <<1,SubBin/binary,3.5/float>>,
    ?line if
	      B =:= <<1,SubBin/binary,3.5/float>> -> ok
	  end.

old_guard_tests(Config) when list(Config) ->
    %% Check that all the old guard tests are still recognized.
    ?line list = og(Config),
    ?line atom = og(an_atom),
    ?line binary = og(<<1,2>>),
    ?line float = og(3.14),
    ?line integer = og(43),
    ?line a_function = og(fun() -> ok end),
    ?line pid = og(self()),
    ?line reference = og(make_ref()),
    ?line tuple = og({}),

    ?line number = on(45.333),
    ?line number = on(-19),
    ok.

og(V) when atom(V) -> atom;
og(V) when binary(V) -> binary;
og(V) when float(V) -> float;
og(V) when integer(V) -> integer;
og(V) when function(V) -> a_function;
og(V) when list(V) -> list;
og(V) when pid(V) -> pid;
og(V) when port(V) -> port;
og(V) when reference(V) -> reference;
og(V) when tuple(V) -> tuple;
og(_) -> what.

on(V) when number(V) -> number;
on(_) -> not_number.

gbif(Config) when is_list(Config) ->
    ?line error = gbif_1(1, {false,true}),
    ?line ok = gbif_1(2, {false,true}),
    ok.

gbif_1(P, T) when element(P, T) -> ok;
gbif_1(_, _) -> error.


t_is_boolean(Config) when is_list(Config) ->
    ?line true = is_boolean(true),
    ?line true = is_boolean(false),
    ?line true = is_boolean(id(true)),
    ?line true = is_boolean(id(false)),

    ?line false = is_boolean(glurf),
    ?line false = is_boolean(id(glurf)),

    ?line false = is_boolean([]),
    ?line false = is_boolean(id([])),
    ?line false = is_boolean(42),
    ?line false = is_boolean(id(-42)),

    ?line false = is_boolean(math:pi()),
    ?line false = is_boolean(384793478934378924978439789873478934897),

    ?line false = is_boolean(id(self())),
    ?line false = is_boolean(id({x,y,z})),
    ?line false = is_boolean(id([a,b,c])),
    ?line false = is_boolean(id(make_ref())),
    ?line false = is_boolean(id(<<1,2,3>>)),

    ?line ok = bool(true),
    ?line ok = bool(false),
    ?line ok = bool(id(true)),
    ?line ok = bool(id(false)),

    ?line error = bool(glurf),
    ?line error = bool(id(glurf)),

    ?line error = bool([]),
    ?line error = bool(id([])),
    ?line error = bool(42),
    ?line error = bool(id(-42)),

    ?line error = bool(math:pi()),
    ?line error = bool(384793478934378924978439789873478934897),

    ?line error = bool(id(self())),
    ?line error = bool(id({x,y,z})),
    ?line error = bool(id([a,b,c])),
    ?line error = bool(id(make_ref())),
    ?line error = bool(id(<<1,2,3>>)),

    ok.

bool(X) when is_boolean(X) -> ok;
bool(_) -> error.


is_function_2(Config) when is_list(Config) ->
    true = is_function(id(fun ?MODULE:all/1), 1),
    true = is_function(id(fun() -> ok end), 0),
    false = is_function(id(fun ?MODULE:all/1), 0),
    false = is_function(id(fun() -> ok end), 1),

    F = fun(_) -> ok end,
    if
	is_function(F, 1) -> ok
    end.

tricky(Config) when is_list(Config) ->
    ?line not_ok = tricky_1(1, 2),
    ?line not_ok = tricky_1(1, blurf),
    ?line not_ok = tricky_1(foo, 2),
    ?line not_ok = tricky_1(a, b),

    ?line false = rb(100000, [1], 42),
    ?line true = rb(100000, [], 42),
    ?line true = rb(555, [a,b,c], 19),
    ok.

tricky_1(X, Y) when abs((X == 1) or (Y == 2)) -> ok;
tricky_1(_, _) -> not_ok.

%% From dets_v9:read_buckets/11, simplified.

rb(Size, ToRead, SoFar) when SoFar + Size < 81920; ToRead == [] -> true;
rb(_, _, _) -> false.


-define(T(Op,A,B),
	ok = if A Op B -> ok; true -> error end,
	ok = if not (A Op B) -> error; true -> ok end,
	(fun(X, Y, True, False) ->
		 ok = if X Op Y -> ok; true -> error end,
		 ok = if False; X Op Y; False -> ok; true -> error end,
		 ok = if X Op Y, True -> ok; true -> error end,
		 ok = if not (X Op Y) -> error; true -> ok end,
		 ok = if False; not (X Op Y); False -> error; true -> ok end
	 end)(id(A), id(B), id(true), id(false))).

-define(F(Op,A,B),
	ok = if A Op B -> error; true -> ok end,
	ok = if not (A Op B) -> ok; true -> error end,
	(fun(X, Y, True, False) ->
		 ok = if X Op Y -> error; true -> ok end,
		 ok = if False; X Op Y; False -> error; true -> ok end,
		 ok = if not (X Op Y); False -> ok; true -> error end,
		 ok = if not (X Op Y), True -> ok; true -> error end
	 end)(id(A), id(B), id(true), id(false))).


rel_ops(Config) when is_list(Config) ->
    ?line ?T(=/=, 1, 1.0),
    ?line ?F(=/=, 2, 2),
    ?line ?F(=/=, {a}, {a}),

    ?line ?F(/=, a, a),
    ?line ?F(/=, 0, 0.0),
    ?line ?T(/=, 0, 1),
    ?line ?F(/=, {a}, {a}),

    ?line ?T(==, 1, 1.0),
    ?line ?F(==, a, {}),

    ?line ?F(=:=, 1, 1.0),
    ?line ?T(=:=, 42.0, 42.0),

    ?line ?F(>, a, b),
    ?line ?T(>, 42, 1.0),
    ?line ?F(>, 42, 42.0),

    ?line ?T(<, a, b),
    ?line ?F(<, 42, 1.0),
    ?line ?F(<, 42, 42.0),

    ?line ?T(=<, 1.5, 5),
    ?line ?F(=<, -9, -100.344),
    ?line ?T(=<, 42, 42.0),

    ?line ?T(>=, 42, 42.0),
    ?line ?F(>=, a, b),
    ?line ?T(>=, 1.0, 0),

    ok.

-undef(TestOp).

basic_andalso_orelse(Config) when is_list(Config) ->
    ?line T = id({type,integers,23,42}),
    ?line 65 = if
		   ((element(1, T) =:= type) andalso (size(T) =:= 4) andalso
		    element(2, T) == integers) ->
		       element(3, T) + element(4, T);
		   true -> error
	       end,
    ?line 65 = case [] of
		   [] when ((element(1, T) =:= type) andalso (size(T) =:= 4) andalso
			    element(2, T) == integers) ->
		       element(3, T) + element(4, T)
	       end,

    ?line 42 = basic_rt({type,integers,40,2}),
    ?line 5.0 = basic_rt({vector,{3.0,4.0}}),
    ?line 20 = basic_rt(['+',3,7]),
    ?line {'Set',a,b} = basic_rt({{'Set',a,b},{'Set',a,b}}),
    ?line 12 = basic_rt({klurf,4}),

    ?line error = basic_rt({type,integers,40,2,3}),
    ?line error = basic_rt({kalle,integers,40,2}),
    ?line error = basic_rt({kalle,integers,40,2}),
    ?line error = basic_rt({1,2}),
    ?line error = basic_rt([]),

    RelProdBody =
	fun(R1, R2) ->
		if
		    (erlang:size(R1) =:= 3) andalso (erlang:element(1,R1) =:= 'Set'),
		    (erlang:size(R2) =:= 3) andalso (erlang:element(1,R2) =:= 'Set') ->
			ok
		end
	end,

    ?line ok = RelProdBody({'Set',a,b}, {'Set',a,b}),
    ok.

basic_rt(T) when is_tuple(T) andalso size(T) =:= 4 andalso element(1, T) =:= type andalso
		 element(2, T) == integers ->
    element(3, T) + element(4, T);
basic_rt(T) when is_tuple(T) andalso size(T) =:= 2 andalso element(1, T) =:= vector ->
    {X,Y} = element(2, T),
    if
	is_float(X), is_float(Y) ->
	    math:sqrt(X*X+Y*Y)
    end;
basic_rt(['+',A,B]) ->
    2*id(A+B);
basic_rt({R1,R2}) when erlang:size(R1) =:= 3 andalso erlang:element(1,R1) =:= 'Set',
		       erlang:size(R2) =:= 3 andalso erlang:element(1,R2) =:= 'Set' ->
    R1 = id(R1),
    R2 = id(R2),
    R1;
basic_rt(T) when is_tuple(T) andalso size(T) =:= 2 andalso element(1, T) =:= klurf ->
    3*id(element(2, T));
basic_rt(_) ->
    error.

traverse_dcd(Config) when is_list(Config) ->
    L0 = [{log_header,dcd_log,"1.0",a,b,c},{log_header,dcd_log,"2.0",a,b,c},
	  {log_header,dcd_log,"0.0",a,b,c},blurf],
    {cont,[{log_header,dcd_log,"0.0",a,b,c},blurf],log,funny} =
	traverse_dcd({cont,L0}, log, funny),
    L1 = [{log_header,dcd_log,"1.0"}],
    {cont,L1,log,funny} = traverse_dcd({cont,L1}, log, funny),
    L2 = [{a,tuple}],
    {cont,L2,log,funny} = traverse_dcd({cont,L2}, log, funny),
    ok.

%% The function starts out with 3 arguments in {x,0}, {x,1}, {x,2}.
%% The outer match of a two tuple will places the first element in {x,3} and
%% second in {x,4}. The guard for the first clause must make ensure that all of those
%% registers are restored befor entering the second clause.
%%
%% (From mnesia_checkpoint.erl, modified.)

traverse_dcd({Cont,[LogH|Rest]},Log,Fun)
  when is_tuple(LogH) andalso size(LogH) =:= 6 andalso element(1, LogH) =:= log_header
andalso erlang:element(2,LogH) == dcd_log,
is_tuple(LogH) andalso size(LogH) =:= 6 andalso element(1, LogH) =:= log_header
andalso erlang:element(3,LogH) >= "1.0" ->
    traverse_dcd({Cont,Rest},Log,Fun);
traverse_dcd({Cont,Recs},Log,Fun) ->
    {Cont,Recs,Log,Fun}.


check_qlc_hrl(Config) when is_list(Config) ->
    St = {r1,false,dum},
    ?line foo = cqlc(qlc, q, [{lc,1,2,3}], St),
    ?line foo = cqlc(qlc, q, [{lc,1,2,3},b], St),
    ?line St = cqlc(qlc, q, [], St),
    ?line St = cqlc(qlc, blurf, [{lc,1,2,3},b], St),
    ?line St = cqlc(q, q, [{lc,1,2,3},b], St),
    ?line St = cqlc(qlc, q, [{lc,1,2,3},b,c], St),
    ?line St = cqlc(qlc, q, [a,b], St),
    ?line {r1,true,kalle} = cqlc(qlc, q, [{lc,1,2,3},b], {r1,true,kalle}),
    ok.

%% From erl_lint.erl; original name was check_qlc_hrl/4.
cqlc(M, F, As, St) ->
    Arity = length(As),
    case As of
        [{lc,_L,_E,_Qs}|_] when M =:= qlc, F =:= q,
                                Arity < 3,
                                not (((element(1, St) =:= r1) orelse fail) and (size(St) =:= 3) and element(2, St)) ->
            foo;
        _ ->
            St
    end.



%% Call this function to turn off constant propagation.
id(I) -> I.

check(F, Result) ->
    case F() of
	Result -> ok;
	Other ->
	    io:format("Expected: ~p\n", [Result]),
	    io:format("     Got: ~p\n", [Other]),
	    test_server:fail()
    end.
