05:34 <emilbayes> This example mentions callbacks as a possible way to handle a reply from an async operation: https://github.com/ponylang/ponyc/blob/493cc93a072fefefe98219c20cb6019d0d1e931a/examples/producer-consumer/main.pony#L7

05:35 <emilbayes> I haven't been able to find anything on callbacks in any of the official pony repos, only the C FFI callbacks. Is what's meant a lambda like in Node.js or did the author have something else in mind?

05:35 <emilbayes> Oh, ping SeanTAllen. Seems you wrote this example :)

07:14 <doublec> emilbayes: a lambda was meant I believe

07:14 <doublec> emilbayes: I wrote a bit about the options here https://bluishcoder.co.nz/2016/05/11/exploring-actors-in-pony.html

07:14 <doublec> emilbayes: (see the simulating return values section)

12:27 <SeanTAllen> emilbayes: or simply passing a tag reference to yourself.

12:27 <SeanTAllen> if there's a known protocol

12:27 <SeanTAllen> for example

12:27 <SeanTAllen> actor2.foo(this)

12:28 <SeanTAllen> and then in actor2, you can call back into later as:

12:28 <SeanTAllen> savedActor.bar()

14:21 <TwoNotes> How do I display a ByteSeq in gdb? "print *data" says "No data fields"

14:25 <Praetonus> A ByteSeq is an interface type, so the compiler can't generate debug info for its fields

14:26 <Praetonus> However, A ByteSeq is either an Array[U8] or a String and these types have the same binary layout

14:26 <TwoNotes> Can Debug.out() print it?

14:26 <Praetonus> So you should be able to cast a ByteSeq to an Array[U8] inside of gdb to print it

14:27 <Praetonus> Something like `print *(Array_U8_val*)(myByteSeq)

14:27 <TwoNotes> Well, that gives me the fields. Now to see the string

14:28 <Praetonus> It is stored in the _ptr field

14:31 <Praetonus> It looks like you have to cast it to char*

14:33 <TwoNotes> Can't display it with Debug.out because Array[U8] does not have a "string" method

14:36 <Praetonus> I got it with gdb

14:36 <Praetonus> `print (char*)((Array_U8_val*)(myByteSeq)->_ptr)`

14:36 <TwoNotes> yikes

14:38 <TwoNotes> Need extra parens around (Array_U8_val*)(data)

14:39 <Praetonus> Yeah, sorry

14:40 <TwoNotes> Maybe Debug could be made to understand Array[U8] and do something with it

14:54 <TwoNotes> I just got the first "Hello world!" HTML page from my new streaming HTTP server project.

14:54 <TwoNotes> Now to debug all the edge cases

23:22 <emilbayes> doublec SeanTAllen thanks guys! How about error handling / propagating errors? Is that sending a primitive (enum) along?

23:25 <emilbayes> Oh right, so that's where promises come in handy. What if I need to call multiple times like a notifier object?

23:47 <doublec> emilbayes: if it needs to call back multiple times then a notifier object would be a good approach

23:48 <doublec> emilbayes: similar to how the net package works

23:48 <emilbayes> doublec: saw that on your blog ^^ didn't see anything on error handling in that case though?

23:54 <emilbayes> And how do you distinguish errors?

23:58 <SeanTAllen> what sort of errors emilbayes?

23:58 <SeanTAllen> the net notify's handle errors as well, if by errors you mean "unable to connect" and things of that sort.

23:59 <emilbayes> Yeah, that's what I was thinking. How do you get the cause of the error though, given that errors don't have an instance or type