I failed to mention: I am using vscode with https://github.com/elixir-lsp/elixir-ls. I don't know if the experience mentioned above differs when using other editors/plugins.
On Monday, May 4, 2020 at 5:37:14 PM UTC-6, Dallin Osmun wrote: > > I propose that we add `IO.error/2` which matches the signature of > `IO.warn/2`. It emits error diagnostics/messages instead of warnings and it > causes the compile step to finish with :error. > > > *Reasoning* > > Often when building a macro you'll do some validation and `raise` an error > if something isn't right. This creates a poor experience for the person > using the macro for two reasons: > 1. You can only raise one error at a time > 2. You don't get a good picture of where the error is because your whole > editor turns red > > You can solve both of those problems by using `IO.warn/2`. You can emit > multiple warnings in a single compile step and you can pass in a stacktrace > which gets turned into a Compiler Diagnostic that in turn, creates good > editor hints. But now the compilation succeeds and you're left in a bad > state. > > I think it is useful to see multiple errors at a time because it shortens > the feedback loop. It also gives more context and can help you realize > where the root cause of your issue lies. > > I think it would be useful to have a function that shared the properties > of `IO.warn/2` and `raise/1`: > - I can emit multiple messages during a single compilation run > - These messages are output as Compiler Diagnostic errors > - Invoking this function will ultimately cause the compilation step to > result in an :error > > > *Examples* > > Today in Ecto Query, this snippet will cause the entire file to turn red > because we mistakenly used sort_by instead of order_by. > query p in Product, sort_by: p.price > > Lets assume we forgot to load the :user type in this Absinthe Schema. We > have two errors but only one gets displayed. Once again, the entire editor > turns red. If instead we saw each line that referenced :user turn red it > might remind us more quickly that we forgot to call `import_types > MyApp.UserTypes`. > query name: "Query" do > field :user, :user, resolve: &MyApp.Users.get_user/3 > ... > field :users, list_of(:user), resolve: &MyApp.Users.list_user/3 > ... > end > > I'm currently working on a library to create GraphQL queries. I can detect > three errors in the following snippet. Today I can only report one at a > time and am greeted with the wall of red. If I switch to `IO.warn/2` I can > report them all and see nice editor hints but my user is left with broken > code after compile. > query do > user(id: "should_be_a_number") do # wrong type for id > firstNam # misspelled, should be firstName > lastName do # lastName should not have a do...end block > name > end > end > end > > > *Code* > > Here is a patch that adds `IO.error/2`: > https://github.com/elixir-lang/elixir/compare/master...numso:io-error > > -- You received this message because you are subscribed to the Google Groups "elixir-lang-core" group. To unsubscribe from this group and stop receiving emails from it, send an email to elixir-lang-core+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/elixir-lang-core/4db1a159-588c-4edb-8417-7d9b9941c92b%40googlegroups.com.
