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-module(dict_use).
-export([ok1/0, ok2/0, ok3/0, ok4/0, ok5/0, ok6/0]).
-export([middle/0]).
-export([w1/0, w2/0, w3/0, w4/1, w5/0, w6/0, w7/0, w8/1, w9/0]).
-define(DICT, dict).
%%---------------------------------------------------------------------
%% Cases that are OK
%%---------------------------------------------------------------------
ok1() ->
dict:new().
ok2() ->
case dict:new() of X -> X end.
ok3() ->
Dict1 = dict:new(),
Dict2 = dict:new(),
Dict1 =:= Dict2.
ok4() ->
dict:fetch(foo, dict:new()).
ok5() -> % this is OK since some_mod:new/0 might be returning a dict:dict()
dict:fetch(foo, some_mod:new()).
ok6() ->
dict:store(42, elli, dict:new()).
middle() ->
{w1(), w2()}.
%%---------------------------------------------------------------------
%% Cases that are problematic w.r.t. opacity of types
%%---------------------------------------------------------------------
w1() ->
gazonk = dict:new().
w2() ->
case dict:new() of
[] -> nil;
42 -> weird
end.
w3() ->
try dict:new() of
[] -> nil;
42 -> weird
catch
_:_ -> exception
end.
w4(Dict) when is_list(Dict) ->
Dict =:= dict:new();
w4(Dict) when is_atom(Dict) ->
Dict =/= dict:new().
w5() ->
case dict:new() of
D when length(D) =/= 42 -> weird;
D when is_atom(D) -> weirder;
D when is_list(D) -> gazonk
end.
w6() ->
is_list(dict:new()).
w7() ->
dict:fetch(foo, [1,2,3]).
w8(Fun) ->
dict:merge(Fun, 42, [1,2]).
w9() ->
dict:store(42, elli,
{dict,0,16,16,8,80,48,
{[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[]},
{{[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[]}}}).
|
