Rustdoc should show output of examples

[huonw]

e.g. std::path has an example that println!'s 3 things, but the user has to copy-paste and then wrap it in fn main() {} to actually see them.

[huonw]

cc @alexcrichton, @cmr

[alexcrichton]

I'm a little confused, what's an example of what you're thinking about? Are you thinking that you can mouse-over to see the output? Rustdoc should inject the output?

[huonw]

The example on std::path could look something like:

---

let mut path = Path::new("/tmp/path");
println!("path: {}", path.display());
path.set_filename("foo");
path.push("bar");
println!("new path: {}", path.display());
println!("path exists: {}", path.exists());

Output

path: /tmp/path
new path: /tmp/foo/bar
path exists: false

---

Mouse-over vs. including it directly etc. can be decided by someone else. There's also been a suggestion of having editable/runnable examples in the tutorial (etc.) using a sandbox similar to the one IRC-rusti has; we could possibly do something similar for docs which would solve this (but then our docs are reliant on a rustc backend to see everything, not standalone).

[brson]

There are two separate issues here: one is just making available the output of all examples, and the other is providing a tool with which authors can insert code blocks that contain the output of examples.

[steveklabnik]

I like linking to the sandbox rather than printing it out.

[emberian]

I agree, I think the sandbox is a lot more valuable and simple here. Do you agree, @huonw?

[emberian]

I think the existence of the sandbox and that all code examples now linking to it closes this.