Fix lines over 80 columns.

src/diag.md

@@ -11,9 +11,9 @@ HIR and MIR, allowing for more informative error reporting.
 
 [span]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax/source_map/struct.Span.html
 
-A `Span` can be looked up in a [`SourceMap`][sourcemap] to get a "snippet" useful
-for displaying errors with [`span_to_snippet`][sptosnip] and other similar
-methods on the `SourceMap`.
+A `Span` can be looked up in a [`SourceMap`][sourcemap] to get a "snippet"
+useful for displaying errors with [`span_to_snippet`][sptosnip] and other
+similar methods on the `SourceMap`.
 
 [sourcemap]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax/source_map/struct.SourceMap.html
 [sptosnip]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax/source_map/struct.SourceMap.html#method.span_to_snippet

src/the-parser.md

@@ -23,9 +23,10 @@ The `syntax` crate contains several main players,
   nodes.
 
 The main entrypoint to the parser is via the various `parse_*` functions in the
-[parser module]. They let you do things like turn a [`SourceFile`][sourcefile] (e.g.
-the source in a single file) into a token stream, create a parser from the
-token stream, and then execute the parser to get a `Crate` (the root AST node).
+[parser module]. They let you do things like turn a [`SourceFile`][sourcefile]
+(e.g. the source in a single file) into a token stream, create a parser from
+the token stream, and then execute the parser to get a `Crate` (the root AST
+node).
 
 To minimise the amount of copying that is done, both the `StringReader` and
 `Parser` have lifetimes which bind them to the parent `ParseSess`. This contains