3 ms·

I was thinking of generic functions rather than (non-generic) methods on generic types. Unfortunately it looks like reflection can’t look up functions in a modu

I was thinking of generic functions rather than (non-generic) methods on generic types. Unfortunately it looks like reflection can’t look up functions in a module at all, which is surprisingly broken.

masklinn 5y ago
> Unfortunately it looks like reflection can’t look up functions in a module at all, which is surprisingly broken. The more time passes the more I think ubiquitous reflection in statically typed languages is what's broken (and a reflection (heh) of deep limitations of the language). So while I could understand having issues with generics breaking existing reflection code (which doesn't seem to be the case), I'm not going to be sad over reflection having never supported toplevel functions in the first place.
- erik_seaberg 5y ago
  What good are top-level functions if they’re unreachable from any script interpreter or management RPC server or other languages’ FFI?
  - 4ad 5y ago
    Functions are useful because you can call them from your program.
  - masklinn 5y ago
    I fail to see what any of this has to do with reflection. > any script interpreter What are you even talking about. > or management RPC server I would very much expect RPC endpoints to be opted in explicitly and statically. > or other languages’ FFI? I fail to see why Go-level reflection would be involved in that in any capacity. > What good are top-level functions You can call them? From your go code? Are you saying rust or C can't be because they don't have reflection? That's a strange position.
    - erik_seaberg 5y ago
      When I type at a Groovy REPL, an interpreter is using reflection for nearly everything. Same goes for native code that has to use reflection via JNI entry points to call Java. It’s damn useful. At the heart of every debugger is a half-finished reflection API that deserves to be cleaned up and surfaced for language interop and novel kinds of tools.
      - pjmlp 5y ago
        Have a look at D and .NET 5 for compile time reflection. Or in Java's case annotation processors. Yes, not everything gets exposed, but it also does the job.

masklinn 5y ago

> Unfortunately it looks like reflection can’t look up functions in a module at all, which is surprisingly broken. The more time passes the more I think ubiquitous reflection in statically typed languages is what's broken (and a reflection (heh) of deep limitations of the language). So while I could understand having issues with generics breaking existing reflection code (which doesn't seem to be the case), I'm not going to be sad over reflection having never supported toplevel functions in the first place.

erik_seaberg 5y ago
What good are top-level functions if they’re unreachable from any script interpreter or management RPC server or other languages’ FFI?
- 4ad 5y ago
  Functions are useful because you can call them from your program.
- masklinn 5y ago
  I fail to see what any of this has to do with reflection. > any script interpreter What are you even talking about. > or management RPC server I would very much expect RPC endpoints to be opted in explicitly and statically. > or other languages’ FFI? I fail to see why Go-level reflection would be involved in that in any capacity. > What good are top-level functions You can call them? From your go code? Are you saying rust or C can't be because they don't have reflection? That's a strange position.
  - erik_seaberg 5y ago
    When I type at a Groovy REPL, an interpreter is using reflection for nearly everything. Same goes for native code that has to use reflection via JNI entry points to call Java. It’s damn useful. At the heart of every debugger is a half-finished reflection API that deserves to be cleaned up and surfaced for language interop and novel kinds of tools.
    - pjmlp 5y ago
      Have a look at D and .NET 5 for compile time reflection. Or in Java's case annotation processors. Yes, not everything gets exposed, but it also does the job.