slepher / erlando Goto Github PK

bug

do_traverse(Monad, F, Node, ChildrenLens) ->
    %% do form
    %% do([Monad ||
    %%           NNode <- F(pre, Node),
    %%           NNNode <- fold_children(Monad, F, NNode, ChildrenLens),
    %%           F(post, NNNode)
    %%    ]).

fold_children use NNode and lens of Node
when Node changes such as from {op, Line, Op, L, R} to {call, Line, Op, [L, R]}
it will use the wrong lens and cause crash

solution

lens should be generated by node
not pre-generated
it's a little complicated
I will do this later.

for now, do not change node structure in pre traverse, use post traverse instead

module type in otp_r18
R18
t_module() -> t_sup(t_atom(), t_parameterized_module()).

module type in otp_r19
R19
t_module() -> t_atom().

cause dialyzer process fail

The call Monad:'>>='(X::any(),Fun::any()) requires that Monad is of type atom()

There will be a parse_transform to fix this.

current type pattern match interface is

-erlando_type({error_m, [{ok, '_'}, {error, '_'}]}). 

will be convert to such pattern match in typeclass module

type({ok, _}) ->
  error_m; 
type({error, _}) ->
  error_m;

so these features are not supported

• record used in pattern match
• function guard test used in pattern match

there should have a better interface for type instance pattern match

Could you provide an example how to combine a state_t and error_t monad, please?

What I'm looking for is that my function can return either {ok, {Result, NewState}}, {ok NewState} or {error, Error}.