linkchecker: Fix checking links which are just fragments
Also fix a typo which linkchecker should have caught.
@@ -650,15 +650,15 @@ Rust syntax is restricted in two ways:
[RFC 550]: https://github.com/rust-lang/rfcs/blob/master/text/0550-macro-future-proofing.md
-## Procedrual Macros
+## Procedural Macros
-"Procedrual macros" are the second way to implement a macro. For now, the only
+"Procedural macros" are the second way to implement a macro. For now, the only
thing they can be used for is to implement derive on your own types. See
[the book][procedural macros] for a tutorial.
Procedural macros involve a few different parts of the language and its
standard libraries. First is the `proc_macro` crate, included with Rust,
-that defines an interface for building a procedrual macro. The
+that defines an interface for building a procedural macro. The
`#[proc_macro_derive(Foo)]` attribute is used to mark the the deriving
function. This function must have the type signature:
