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> homoiconicity (data structure syntax)

Can someone explain to me why we need a murky word like "homoiconicity" and then explain it as "data structure syntax" (which doesn't clarify much) when "self-modifying code" and "metaprogramming" are crystal clear?

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Homoiconicity means you're code is defined in terms of the same data structures that are used in programs written in the language. This makes self-modifying code and metaprogramming easier because the language's standard library is already full of functions that operate on those data structures.

However, you can have self-modifying code and metaprogramming without homoiconicity, and you can have homoiconicity without support for self-modifying code and metaprogramming.

Both "self-modifying code" and "metaprogramming" don't mean exactly the same thing to me as "homoiconicity"

I guess I need to learn Lisp to understand the distinction. My only reference is XLST which is also valid XML.

https://en.wikipedia.org/wiki/Homoiconicity

Well, it depends on your exact definition of "self-modifying code" and "metaprogramming", given that it's not like there's an authoratative source you can look up the definitions in. The way I understand the term without additional context, XLST is not "self-modifying code" in the same way malware, certain JIT implementation techniques etc are.

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