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I think you're describing what Fowler[1] calls an "external" dsl ie separate lexer, parser, and code generator. The alternative being "internal" dsl, something that uses a languages own constructs to create stuff; ie like how Ruby is is used in several well known frameworks.

[1] https://www.goodreads.com/book/show/8082269-domain-specific-...

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I think this is still applicable advice for embedded DSLs too, since the grammar of the DSL will be made up of the ways in which you can compose the operations you provide, whether they are parsed by the host language's parser or your own.

Overall, I agree that it's important to think about how to make sure that operations compose in an unintuitive, expected way. I find this hard to figure out without thinking of it in terms of a grammar and semantics, whether it's embedded or not.

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