leandroluk
Dialyzer shows the warning "The pattern can never match the type" on create a basic Phoenix api
I created a project using the command:
mix phx.new elixir_api \
--no-assets \
--no-dashboard \
--no-ecto \
--no-gettext \
--no-html \
--no-mailer \
--binary-id
Then I opened the project in VSCode and browsed to the file ./lib/elixir_api_web/router.ex and the IDE shows me a warning like this:
The pattern can never match the type.
Pattern:
{_, _, _, _}
Type:
:error
ElixirLS Dialyzer
The file has only the automatically generated code. Why is this warning appearing then, since when running the application it doesn’t bring me any warning messages?
Most Liked
al2o3cr
That message appears to be related to --no-html, based on the last comment here:
https://github.com/phoenixframework/phoenix/issues/5375#issuecomment-1479898484
3
rlopzc
TL;DR: You can’t have an empty scope statement (no routes) in router.ex
2
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