As a long time lisper I don't think homoiconicity is that relevant, at least when comparing lisps with other programming language. What I miss when writing C++ is the incremental compilation model of lisps, and in particular the ability to have compile time data drive code generation.
Homoiconicity is more useful when comparing lisps IMO, and pondering on how they could be improved. To me, homoiconicity is a constant struggle and should be appreciated in degrees because homoiconicity is about immediacy.
A lisp that doesn't allow you to embed data along with code, JSON/Javascript style, is less homoiconic than a language that does, and it's more about what the core library allows than the language itself. For instance I'd say Clojure is more homoiconic than Scheme because it allows you to embed hashmaps in your code natively, whereas in scheme you only have `(make-hash-table)` without the corresponding reader macro. Similarly, a lisp without syntax quote would be less homoiconic than one that has it.
This is why I say it's about immediacy. When you don't have to deal with hashmaps, or templated s-exprs in terms of the process that builds them, the mediation layer disappears.
Things I'd like to be more immediate in Clojure:
- keeping track of whitespaces within s-exprs. Useful when you want to print code as it is indented in the source file. There's a library for that (rewrite-clj), but it isn't integrated in the reader+compiler pipeline, so it's a bit of an headache as you have to read code from files, which implies, bridging the gap between the compilation pipeline and this library on your own.
- accessing semantic info within macros. Which functions use which variables. Which variables are global vs local (in particular when lexically shadowed), which variables are closed over by which lambdas, etc. To do this you have to use clojure.core.analyzer, which is very complex and poorly documented: not immediate enough.
Homoiconicity is more useful when comparing lisps IMO, and pondering on how they could be improved. To me, homoiconicity is a constant struggle and should be appreciated in degrees because homoiconicity is about immediacy.
A lisp that doesn't allow you to embed data along with code, JSON/Javascript style, is less homoiconic than a language that does, and it's more about what the core library allows than the language itself. For instance I'd say Clojure is more homoiconic than Scheme because it allows you to embed hashmaps in your code natively, whereas in scheme you only have `(make-hash-table)` without the corresponding reader macro. Similarly, a lisp without syntax quote would be less homoiconic than one that has it.
This is why I say it's about immediacy. When you don't have to deal with hashmaps, or templated s-exprs in terms of the process that builds them, the mediation layer disappears.
Things I'd like to be more immediate in Clojure:
- keeping track of whitespaces within s-exprs. Useful when you want to print code as it is indented in the source file. There's a library for that (rewrite-clj), but it isn't integrated in the reader+compiler pipeline, so it's a bit of an headache as you have to read code from files, which implies, bridging the gap between the compilation pipeline and this library on your own.
- accessing semantic info within macros. Which functions use which variables. Which variables are global vs local (in particular when lexically shadowed), which variables are closed over by which lambdas, etc. To do this you have to use clojure.core.analyzer, which is very complex and poorly documented: not immediate enough.