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Convert JSON data into Elm type aliases and record definitions. Generate accurate data model code instantly for Elm developers.
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Automatically convert JSON data into C# class definitions, ideal for .NET developers building data models.
When Elm developers need to process JSON data returned by external APIs, manually writing type definitions is both tedious and error-prone. By parsing your input JSON string, this tool automatically identifies its structure, key-value types, and nested relationships to generate type alias and record definitions that comply with Elm syntax standards. Elm type definitions are the core mechanism for ensuring data consistency and compile-time safety in strongly typed languages. The code output by this tool can be used directly to build data models in your Elm projects.
Q: What Elm type will null values in JSON be converted to?
A: Null values are mapped to Elm's Maybe type (e.g., Maybe String), indicating that the field is optional.
Q: Can this tool generate a Json.Decoder?
A: No. This tool only generates type definitions. To actually parse JSON, you need to write a decoder using Elm's Json.Decode module.
Please ensure that the input JSON format is valid and avoid errors such as missing quotes or commas. The tool automatically infers Int or Float types based on whether a number contains a decimal, but manual adjustments may still be required. If the generated field names do not match your JSON key naming style, you will need to modify them manually to comply with Elm naming conventions.
For complex API responses, we recommend using a JSON validator first to ensure the data format is correct. For example, inputting {"name": "Alice", "age": 30, "tags": ["user", "vip"]} will output: type alias Model = { name : String, age : Int, tags : List String }. This conversion significantly reduces manual coding errors and boosts Elm development efficiency.
