### A quick tour of Rustfmt
-Rustfmt is basically a pretty printer - that is, it's mode of operation is to
+Rustfmt is basically a pretty printer - that is, its mode of operation is to
take an AST (abstract syntax tree) and print it in a nice way (including staying
under the maximum permitted width for a line). In order to get that AST, we
first have to parse the source text, we use the Rust compiler's parser to do
-that (see [src/lib.rs]). We shy away from doing anything too fancy, such as
+that (see [src/lib.rs](src/lib.rs)). We shy away from doing anything too fancy, such as
algebraic approaches to pretty printing, instead relying on an heuristic
approach, 'manually' crafting a string for each AST node. This results in quite
a lot of code, but it is relatively simple.
'top level' items. Then we can reproduce that text pretty much verbatim. We only
count spans we actually reformat, so if we can't format a span it is not missed
completely, but is reproduced in the output without being formatted. This is
-mostly handled in [src/missed_spans.rs]. See also `FmtVisitor::last_pos` in
-[src/visitor.rs].
+mostly handled in [src/missed_spans.rs](src/missed_spans.rs). See also `FmtVisitor::last_pos` in
+[src/visitor.rs](src/visitor.rs).
#### Some important elements
At the highest level, Rustfmt uses a `Visitor` implementation called `FmtVisitor`
-to walk the AST. This is in [src/visitor.rs]. This is really just used to walk
+to walk the AST. This is in [src/visitor.rs](src/visitor.rs). This is really just used to walk
items, rather than the bodies of functions. We also cover macros and attributes
here. Most methods of the visitor call out to `Rewrite` implementations that
then walk their own children.
-The `Rewrite` trait is defined in [src/rewrite.rs]. It is implemented for many
+The `Rewrite` trait is defined in [src/rewrite.rs](src/rewrite.rs). It is implemented for many
things that can be rewritten, mostly AST nodes. It has a single function,
`rewrite`, which is called to rewrite `self` into an `Option<String>`. The
arguments are `width` which is the horizontal space we write into, and `offset`
into the required width. How to handle this is up to the caller. Often the
caller just gives up, ultimately relying on the missed spans system to paste in
the un-formatted source. A better solution (although not performed in many
-places) is for the caller to shuffle around some of it's other items to make
+places) is for the caller to shuffle around some of its other items to make
more width, then call the function again with more space.
Since it is common for callers to bail out when a callee fails, we often use a
array elements, etc. We have some generic code to handle lists, including how to
space them in horizontal and vertical space, indentation, comments between
items, trailing separators, etc. However, since there are so many options, the
-code is a bit complex. Look in [src/lists.rs]. `write_list` is the key function,
+code is a bit complex. Look in [src/lists.rs](src/lists.rs). `write_list` is the key function,
and `ListFormatting` the key structure for configuration. You'll need to make a
`ListItems` for input, this is usually done using `itemize_list`.
Rustfmt strives to be highly configurable. Often the first part of a patch is
creating a configuration option for the feature you are implementing. All
-handling of configuration options is done in [src/config.rs]. Look for the
+handling of configuration options is done in [src/config.rs](src/config.rs). Look for the
`create_config!` macro at the end of the file for all the options. The rest of
the file defines a bunch of enums used for options, and the machinery to produce
the config struct and parse a config file, etc. Checking an option is done by