feat: added Topic::child method that returns a child topic

[The-Ladle]

Working with this, I needed to access multiple different topics from the same prefix. While I could have simply used a string for my prefix (which is what I am doing now), I figured it would be more intuitive to add a function that returns a "child" topic. Feel free to change anything about this; I am definitely not the best Rust programmer.

[DatAsianBoi123]

That sounds like a valid use-case, though the code doesn't seem to do what you described?

What I interpret a ::child function to do is:

Topic topic = client.topic("/mytopic"); // `/mytopic`
Topic child = topic.child("/suffix"); // `/mytopic/suffix`

But the current implementation that you have only returns a topic with the same name as the argument in ::child.

[DatAsianBoi123]

Also, just a nitpick but I recently switched to using conventional commits as a convention for commit messages, so it would be nice to change that one commit message to follow that convention. Something like feat: added Topic::child method that returns a child topic would be great.

[The-Ladle]

I just realized that I didn't combine the strings 🤦. My bad.

[The-Ladle]

I just fixed the issue. Apologies for the error, and thanks for catching it.

[DatAsianBoi123]

Alright looks good now, just a couple things before I merge:

• The method should return Self, right now it returns ()
• Just for convention's sake, you should be using Self::new instead of Topic::new
• The method can take just a &str since you don't need an owned String
• It would be nice to create documentation examples because it may be unclear what the method does

[The-Ladle]

Thanks for the feedback on the function, as I stated earlier, I'm nowhere near the greatest rust programmer. I assume you're fixing those before merging (with the likely exception of the documentation since that is not crucial)?

[DatAsianBoi123]

I don't have permission to as the pr is merging from your own repo that I don't have write access to.

[The-Ladle]

Ok, I will fix that when I get home and probably write some documentation on what it is for/how to use it.