# `JSONAPI.Deprecation`
[🔗](https://github.com/beam-community/jsonapi/blob/main/lib/jsonapi/deprecation.ex#L1)

  Generate warnings in places where we want to deprecate functions or struct parameters

# `warn`

  Generates a deprecation warning for using `fields[relationship_key]` instead of `fields[type]` when
  parsing query parameters.

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*Consult [api-reference.md](api-reference.md) for complete listing*