Handling Duplicate Alias Warnings in Elm

Elm’s Duplicate Alias Warning is rare but occurs when aliasing imported modules or functions with the same name.

This happens when multiple modules expose similarly named functions or values, and you attempt to alias both in your file.

For example, importing two JSON decoders like import Json.Decode as JD and import MyJson.Decode as JD triggers this warning.

To resolve it, start by ensuring unique aliases for each conflicting module.

Instead of JD, rename one as MyJD.

Use qualified imports (import Json.Decode exposing (..) and Json.Decode.decodeString) where possible to eliminate aliasing entirely.

Next, examine your code for unintentional multiple imports of the same module, which can occur during refactoring.

Elm’s compiler is strict about duplicate declarations to ensure clarity and maintainability.

By adopting unique aliases and reducing unnecessary imports, your Elm codebase will become more modular and error-free.