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Comment by marcosdumay | Hacker News Reader

I always have problems with the definition of homoiconicism...

Prolog code is represented the same way as data, but (AFAIK) there is no functionality for manipulating code at run-time or interpretation-time. I believe allowing macros is a necessary condition for homoiconicism, if I'm right, then Prolog isn't it.

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> there is no functionality for manipulating code at run-time or interpretation-time

Sure there is: http://www.swi-prolog.org/pldoc/man?section=manipterm

Example:

    ?- foo(Bar, Baz) =.. List.
    List = [foo, Bar, Baz].

And:

    ?- F =.. [foo, Bar, Baz].
    F = foo(Bar, Baz).

No, I think just code is data is code right?

Also, I'm not sure macros are needed for a language which doesn't do compilation.

You can do all that with term-rewriting in Prolog, you can use a grammar to parse a file of arbitrary text and transform it into prolog terms to be executed etc

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