shape_mod1.erlt

%% Copyright (c) Facebook, Inc. and its affiliates.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%%     http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.

-module(shape_mod1).

-export([test/0, test/1, test2/1, test_in_lc/1]).

-spec test() -> integer().
[unchecked]
test() ->
    size({#(),
     test3(#(a=1, b=2)),
     test4(#(a=1, b=2)#()),
     test5(#(a=1)#(b=2)#()),
     #(a=1,b=2)#(a),
     #(a=1)#(b=2)#(a),
     #()#(a=1,b=#(c=2,d=3))#(b)#(e=4),
    #(a = 1, b = 2) = mk_map(1,2),
    #(a=2) = update_map1(#(a=1), 2),
    #(a = 2, b = 1) = update_map3(mk_map(1,2)),
    {'x', {25,36}} = access_map(#(id='x', location={25,36})),
    'ok' = access_map2(#(inner1=#(inner2='ok')))}).

-spec test(#(a::integer(), b::#(c::integer()))) -> atom().
test(A) when A =:= #(a=1,b=#(c=2)) -> 'closed_ok';
test(#(a=1,b=#(c=2))) -> 'open_ok'.

-spec test2(#()) -> {}.
test2(#()) -> {}.

test3(A) when A#(b) =:= 2 -> {}.

test4(A) when A =:= #(a=1,b=1)#(b=2) -> {}.

test5(#(a=1)) -> {}.

-spec test_in_lc([#(id::A, _B)]) -> [A].
test_in_lc(List) ->
    [Id || #(id = Id) <- List ].

-spec mk_map(A, B) -> #(a :: A, b :: B).
mk_map(A, B) ->
    #(a = A, b = B).

-spec update_map1(#(a :: A), A) -> #(a :: A).
update_map1(M, A) ->
    M#(a = A).

%% Generic updates are dis-allowed?
%%-spec update_map2(#(a :: A | _), A) -> #(a :: A | _).
%%update_map2(M, A) ->
%%    M#(a = A).

-spec update_map3(#(a :: A, b :: A)) -> #(a :: A, b :: A).
update_map3(M) ->
    A0 = M#(a),
    B0 = M#(b),
    M#(a = B0, b = A0).

%% Generic updates are forbidden?
%%-spec update_map4(#(a :: A, b :: A | _)) -> #(a :: A, b :: A | _).
%%update_map4(M) ->
%%    A0 = M#(a),
%%    B0 = M#(b),
%%    M#(a = B0, b = A0).

-spec access_map(#(id :: Id, location :: Location, _)) -> {Id, Location}.
access_map(M) ->
    {M#(id), M#(location)}.

-spec access_map2(#(inner1 :: #(inner2 :: A))) -> A.
access_map2(M) ->
    M#(inner1)#(inner2).