Playpen links from code snippets on doc.rust-lang.org contain wrong code

[Valloric]

For example, the code snippet for std::str::StrExt::split shows an arrow in the top-right when hovered over with the mouse. The arrow is a link to the following page with suspicious muffin-related content. This seems to be the snippet for the std::str::StrExt::replace function (which is also the first function on the page with example code). All other code snippets on the page lead to the same muffin code.

This is on Chrome 39.0.2171.95 (64-bit) on Mac OS X 10.10.1.

[estsauver]

It looks like this is caused by rustdoc rendering all of the examples with the same id.

If you look at the playpen js code in rustdoc: https://github.com/rust-lang/rust/blob/5b3cd3900ceda838f5798c30ab96ceb41f962534/src/librustdoc/html/static/playpen.js

you see that it depends on all the same ids being different. However, if you look at the source of the StrExt example you linked, you see they all have "rust-example-rendered-0" as the id.

I think the error comes from somewhere in here,

https://github.com/rust-lang/rust/blob/master/src/librustdoc/html/markdown.rs#L196

but it's not obvious to me how to fix it. I'll look into the issue, but this is my first little bit of work on rust so it may take a second/I'd appreciate insight as to what the problem might be.

[Gankra]

nominating for I-muffins