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Diffstat (limited to 'lib/dialyzer/test/small_tests_SUITE_data/src/trec.erl')
| -rw-r--r-- | lib/dialyzer/test/small_tests_SUITE_data/src/trec.erl | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/lib/dialyzer/test/small_tests_SUITE_data/src/trec.erl b/lib/dialyzer/test/small_tests_SUITE_data/src/trec.erl new file mode 100644 index 0000000000..b36b0cafba --- /dev/null +++ b/lib/dialyzer/test/small_tests_SUITE_data/src/trec.erl @@ -0,0 +1,37 @@ +%% +%% The current treatment of typed records leaves much to be desired. +%% These are not made up examples; I have cases like that the branch +%% of the HiPE compiler with types in records. I get very confusing +%% warnings which require a lot of effort to find their cause and why +%% a function has no local return. +%% +-module(trec). +-export([test/0, mk_foo_exp/2]). + +-record(foo, {a :: integer(), b :: [atom()]}). + +%% +%% For these functions we currently get the following warnings: +%% 1. Function test/0 has no local return +%% 2. The call trec:mk_foo_loc(42,any()) will fail since it differs +%% in argument position 1 from the success typing arguments: +%% ('undefined',atom()) +%% 3. Function mk_foo_loc/2 has no local return +%% +%% Arguably, the second warning is not what most users have in mind +%% when they wrote the type declarations in the 'foo' record, so no +%% doubt they'll find it confusing. But note that it is also inconsistent! +%% How come there is a success typing for a function that has no local return? +%% +test() -> + mk_foo_loc(42, bar:f()). + +mk_foo_loc(A, B) -> + #foo{a = A, b = [A,B]}. + +%% +%% For this function we currently get "has no local return" but we get +%% no reason; I want us to get a reason. +%% +mk_foo_exp(A, B) when is_integer(A) -> + #foo{a = A, b = [A,B]}. |