Is possible to generate classes by a macro that loads and parse JSON definition?

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Hello! Is possible to make macro, that loads JSON, parse it and generate classes based on this JSON recipe? I know, that I can load file by the macro - is JSON parsing completely out of the concept of macros? Thanks!

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  1. It’s always possible to achieve this through any build system (Makefile etc.)
  2. In Crystal any code generation is possible through macro run. Just make a program that prints source code “normally”. This is quite heavy, though, and I don’t think it’s parallelized (but it is cached).
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I wonder if it would make sense to translate the JSON schema to Crystal outside of the compilation step, similar to how Protobuf compiles from its source format into language-specific code in a separate step using the protoc tool.

This way you can see exactly what Crystal code you’re generating. That generated code might use macros but it can be a lot easier to read. I’ve never found JSON schemas written in JSON to be very readable as source material, though. :slightly_smiling_face:

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Is this what you are looking for?