Elm Error Handling

Elm Result and Maybe error handling patterns

Default

Language / Topic

Elm

Rules

Elm Error Handling · balanced balanced

- Use `Result` for operations that can fail with meaningful error information and `Maybe` for values that may simply be absent.

- Use `Result.andThen` to chain fallible operations without nested `case` expressions: `validate input |> Result.andThen transform`.

- Define a `Problem` or `Error` custom type per feature with specific constructors instead of using `String` as the error payload.

- Use `Result.map` and `Maybe.map` to transform values inside the container without unwrapping them prematurely.