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> The only language where macros aren't just C's #define to replace text. You're working directly with the AST It's hardly the only such language. In my experi

> The only language where macros aren't just C's #define to replace text. You're working directly with the AST It's hardly the only such language. In my experience, Haskell, Rust, Common Lisp, and Scheme all have macros that operate by syntax trees rather than text substitution, and I have no doubt that there are several more that I'm not aware of.

davidkunz 5y ago
I add: Nim, Crystal
- adenozine 5y ago
  I add Io(defunct), Self, Smalltalk, Tcl...
  - auxym 5y ago
    Eh, Tcl's metaprogramming, as far as I remember, is highly text based. EIAS.
    - jjnoakes 5y ago
      It's mostly based on manipulating lists. Scoping is a bit odd, but if you squint, the fact that unevaluated lists are passed into functions where they can be manipulated (by normal tcl list functions) and then evaluated in the caller's scope (or in other scopes), coupled with the fact that built in syntax (if, proc, for, etc) is the same as user-defined function call syntax, gives you more metaprogramming power than you might expect.
    - adenozine 5y ago
      True, mostly. As the other commenter noted, function calls can be squeezed through some rather macro-looking holes if you just push hard enough. Don't get me wrong, Tcl metaprogramming is awful and gross and I don't recommend it, I was just being the stereotypical nitpick HN commenter for that moment since it CAN be done.
leephillips 5y ago
Julia is another.
gpderetta 5y ago
In fact, which language except C and derivatives has macros that are inky simple token replacement?
- dnautics 5y ago
  Erlang! So you can perhaps sympathize with GP's confusion on the matter.
  - linkdd 5y ago
    I was talking about Elixir's macros. Not Erlang parse_transform.
linkdd 5y ago
AFAIR, Haskell do have metaprogramming but not with macros, I remember reading this[0] a few months ago. Maybe I misread the article? For Rust, I've seen more usage of `macro_rules!` than the other one (so much I did not even know it existed). And it looks a lot like C's #define. But yeah, my bad, I've been a bit too presumptuous when saying Elixir was the only one. [0] - https://chrisdone.com/posts/haskell-doesnt-have-macros/
pjmlp 5y ago
Adding Java and .NET languages, which do it via attributes/annotations, compiler plugins, and T4 templates and code generators. Circle compiler for C++, and D as well.

davidkunz 5y ago

I add: Nim, Crystal

adenozine 5y ago
I add Io(defunct), Self, Smalltalk, Tcl...
- auxym 5y ago
  Eh, Tcl's metaprogramming, as far as I remember, is highly text based. EIAS.
  - jjnoakes 5y ago
    It's mostly based on manipulating lists. Scoping is a bit odd, but if you squint, the fact that unevaluated lists are passed into functions where they can be manipulated (by normal tcl list functions) and then evaluated in the caller's scope (or in other scopes), coupled with the fact that built in syntax (if, proc, for, etc) is the same as user-defined function call syntax, gives you more metaprogramming power than you might expect.
  - adenozine 5y ago
    True, mostly. As the other commenter noted, function calls can be squeezed through some rather macro-looking holes if you just push hard enough. Don't get me wrong, Tcl metaprogramming is awful and gross and I don't recommend it, I was just being the stereotypical nitpick HN commenter for that moment since it CAN be done.

leephillips 5y ago

Julia is another.

gpderetta 5y ago

In fact, which language except C and derivatives has macros that are inky simple token replacement?

dnautics 5y ago
Erlang! So you can perhaps sympathize with GP's confusion on the matter.
- linkdd 5y ago
  I was talking about Elixir's macros. Not Erlang parse_transform.

linkdd 5y ago

AFAIR, Haskell do have metaprogramming but not with macros, I remember reading this[0] a few months ago. Maybe I misread the article? For Rust, I've seen more usage of `macro_rules!` than the other one (so much I did not even know it existed). And it looks a lot like C's #define. But yeah, my bad, I've been a bit too presumptuous when saying Elixir was the only one. [0] - https://chrisdone.com/posts/haskell-doesnt-have-macros/

pjmlp 5y ago

Adding Java and .NET languages, which do it via attributes/annotations, compiler plugins, and T4 templates and code generators. Circle compiler for C++, and D as well.