Multiple responses in a callback

[jailbird777]

I know this is a really dumb question, sorry, as I'm still learning Zig so I'm having a hard time learning from the code itself.

I'm using the sample IRC bot code, and one of the first things I wanted to do was enhance the !help text. Most output is multiline, and the code doesn't automatically handle linebreaks like \r\n in the text, so I tried doing something like:

fn help(prefix: ?zircon.Prefix, targets: []const u8) ?zircon.Message {
_ = zircon.Message{
.PRIVMSG = .{
.targets = if (prefix) |p| p.nick orelse targets else targets,
.text = "Commands are:",
},
};
return = zircon.Message{
.PRIVMSG = .{
.targets = if (prefix) |p| p.nick orelse targets else targets,
.text = "!help (This text)",
},
};
}

But sadly, only the last one ever makes it (the "!help (This text)" one). What stupid thing am I missing?

[vascocosta]

Hello and thank you for your interest in my code!

There are no stupid questions.

In zig, as you probably know, _ is used to discard variables. So the first message you create is basically being discarded, because you bind it to _, instead of some variable name. Nothing happens because you don't really do anything with that message. Besides, the way my library works, only one message can be sent to the server each time a callback is called. The message that is sent, is the message you return from the callback function with the return keyword at the end.

Try using simply "\n" instead of "\r\n". This should work and allow multiple lines, but I'll let you know soon when I get time to test it. If it doesn't, then it means I'll have to change my code to allow an array of messages to be returned from the callback.

[jailbird777]

You're right about the _, I was stupidly thinking that it was only returning a value to see if the message actually made it, since the function itself could only return one value, I figured if the last one "made it", then the others should have. But obviously that's NOT what is being returned, so totally dumb move on my part.

I tried \n and only the first part before the \n makes it. I have a feeling the rest is getting sent without "PRIVMSG target :" to the server and just getting dropped. I'll disable TLS and watch the traffic to verify.

[vascocosta]

Ah, I see why you did what you did now. But no, creating a message in itself doesn't have side effects. It isn't sent, unless returned. I was checking my examples and I never use multi-line messages, so maybe this is something I overlooked and it is not working indeed.

The most obvious solution, if this is the case, is to change my code to split the message returned by the callback into multiple messages internally. This would keep the same API to the user. I'll have a look sometime during this week still.

I should take the chance to make sure the code is working with zig 0.15 as well. I've developed it for version 0.14 and didn't check against the latest version yet.

[jailbird777]

I want to say the only 0.15.1 problems I had was with the build.zig changes, but I'll try again. And thanks for all of the help. I guess that's what I get for actually trying to be lazy and do the help first!