doc: languagues: rust: Reformat

Refill the text to 100 columns instead of 72 to match the rest of the
project.

Signed-off-by: David Brown <[email protected]>

Author: d3zd3z

doc/develop/languages/rust/index.rst

@@ -3,30 +3,25 @@
 Rust Language Support
 #####################
 
-Rust is a systems programming language focused on safety, speed, and
-concurrency. Designed to prevent common programming errors such as
-null pointer dereferencing and buffer overflows, Rust emphasizes
-memory safety without sacrificing performance. Its powerful type
-system and ownership model ensure thread-safe programming, making it
-an ideal choice for developing reliable and efficient low-level code.
-Rust's expressive syntax and modern features make it a robust
-alternative for developers working on embedded systems, operating
-systems, and other performance-critical applications.
+Rust is a systems programming language focused on safety, speed, and concurrency. Designed to
+prevent common programming errors such as null pointer dereferencing and buffer overflows, Rust
+emphasizes memory safety without sacrificing performance. Its powerful type system and ownership
+model ensure thread-safe programming, making it an ideal choice for developing reliable and
+efficient low-level code.  Rust's expressive syntax and modern features make it a robust alternative
+for developers working on embedded systems, operating systems, and other performance-critical
+applications.
 
 Enabling Rust Support
 *********************
 
-Currently, Zephyr supports applications written in Rust and C.  The
-enable Rust support, you must select the :kconfig:option:`CONFIG_RUST`
-in the application configuration file.
+Currently, Zephyr supports applications written in Rust and C.  The enable Rust support, you must
+select the :kconfig:option:`CONFIG_RUST` in the application configuration file.
 
-The rust toolchain is separate from the rest of the Zephyr SDK.   It
-is recommended to use the `rustup`_ tool to install the rust
-toolchain.  In addition to the base compiler, you will need to install
-core libraries for the target(s) you wish to compile on.  It is
-easiest to determine what needs to be installed by trying a build.
-The diagnostics from the rust compilation will indicate the rust
-command needed to install the appropriate target support:
+The rust toolchain is separate from the rest of the Zephyr SDK.   It is recommended to use the
+`rustup`_ tool to install the rust toolchain.  In addition to the base compiler, you will need to
+install core libraries for the target(s) you wish to compile on.  It is easiest to determine what
+needs to be installed by trying a build.  The diagnostics from the rust compilation will indicate
+the rust command needed to install the appropriate target support:
 
 .. _rustup: https://rustup.rs/
 
@@ -39,10 +34,9 @@ command needed to install the appropriate target support:
    = note: the `thumbv7m-none-eabi` target may not be installed
    = help: consider downloading the target with `rustup target add thumb7m-none-eabi`
 
-In this case, the given ``rustup`` command will install the needed
-target support.  The target needed will depend on both the board
-selected, as well as certain configuration choices (such as whether
-floating point is enabled).
+In this case, the given ``rustup`` command will install the needed target support.  The target
+needed will depend on both the board selected, as well as certain configuration choices (such as
+whether floating point is enabled).
 
 Writing a Rust Application
 **************************
@@ -52,8 +46,7 @@ See :zephyr_file:`samples/rust` for examples of an application.
 CMake files
 -----------
 
-The application should contain a :file:`CMakeFiles.txt`, similar to
-the following:
+The application should contain a :file:`CMakeFiles.txt`, similar to the following:
 
 .. code-block:: cmake
 
@@ -67,22 +60,20 @@ the following:
 Cargo files
 -----------
 
-Rust applications are built with Cargo.  The Zephyr build system will
-configure and invoke cargo in your application directory, with options
-set so that it can find the Zephyr support libraries, and that the
-output will be contained within the Zephyr build directory.
+Rust applications are built with Cargo.  The Zephyr build system will configure and invoke cargo in
+your application directory, with options set so that it can find the Zephyr support libraries, and
+that the output will be contained within the Zephyr build directory.
 
-The :file:`Cargo.toml` will need to have a ``[lib]`` section that sets
-``crate-type = ["staticlib"]``, and will need to include ``zephyr =
-"0.1.0"`` as a dependency.  You can use crates.io and the Crate
-ecosystem to include any other dependencies you need.  Just make sure
-that you use crates that support building with no-std.
+The :file:`Cargo.toml` will need to have a ``[lib]`` section that sets ``crate-type =
+["staticlib"]``, and will need to include ``zephyr = "0.1.0"`` as a dependency.  You can use
+crates.io and the Crate ecosystem to include any other dependencies you need.  Just make sure that
+you use crates that support building with no-std.
 
 Application
 -----------
 
-The application source itself should live in file:`src/lib.rs`.  A few
-things are needed.  A minimal file would be:
+The application source itself should live in file:`src/lib.rs`.  A few things are needed.  A minimal
+file would be:
 
 .. code-block:: rust
 
@@ -94,30 +85,25 @@ things are needed.  A minimal file would be:
    extern "C" fn rust_main() {
    }
 
-The ``no_std`` declaration is needed to prevent the code from
-referencing the ``std`` library.  The extern reference will cause the
-zephyr crate to be brought in, even if nothing from it is used.
-Practically, any meaningful Rust application on Zephyr will use
-something from this crate, and this line is not necessary.  Lastly,
-the main declaration exports the main symbol so that it can be called
-by C code.  The build ``rust_cargo_application()`` cmake function will
-include a small C file that will call into this from the C main
-function.
+The ``no_std`` declaration is needed to prevent the code from referencing the ``std`` library.  The
+extern reference will cause the zephyr crate to be brought in, even if nothing from it is used.
+Practically, any meaningful Rust application on Zephyr will use something from this crate, and this
+line is not necessary.  Lastly, the main declaration exports the main symbol so that it can be
+called by C code.  The build ``rust_cargo_application()`` cmake function will include a small C file
+that will call into this from the C main function.
 
 Zephyr Functionality
 ********************
 
-The bindings to Zephyr for Rust are under development, and are
-currently rather minimalistic.
+The bindings to Zephyr for Rust are under development, and are currently rather minimalistic.
 
 Bool Kconfig settings
 ---------------------
 
-Boolean Kconfig settings can be used from within Rust code.  Due to
-design constraints by the Rust language, settings that affect
-compilation must be determined before the build is made.  In order to
-use this in your application, you will need to use the
-``zephyr-build`` crate, provided, to make these symbols available.
+Boolean Kconfig settings can be used from within Rust code.  Due to design constraints by the Rust
+language, settings that affect compilation must be determined before the build is made.  In order to
+use this in your application, you will need to use the ``zephyr-build`` crate, provided, to make
+these symbols available.
 
 To your ``Cargo.toml`` file, add the following:
 
@@ -126,17 +112,16 @@ To your ``Cargo.toml`` file, add the following:
    [build-dependencies]
    zephyr-build = "0.1.0"
 
-Then, you will need a ``build.rs`` file to call the support function.
-The following will work:
+Then, you will need a ``build.rs`` file to call the support function.  The following will work:
 
 .. code-block:: rust
 
    fn main() {
        zephyr_build::export_bool_kconfig();
    }
 
-At this point, it will be possible to use the ``cfg`` directive in
-Rust on boolean Kconfig values.  For example:
+At this point, it will be possible to use the ``cfg`` directive in Rust on boolean Kconfig values.
+For example:
 
 .. code-block:: rust
 
@@ -149,8 +134,8 @@ Rust on boolean Kconfig values.  For example:
 Other Kconfig settings
 ----------------------
 
-All bool, numeric and string Kconfig settings are accessible from the
-``zephyr::kconfig`` module.  For example:
+All bool, numeric and string Kconfig settings are accessible from the ``zephyr::kconfig`` module.
+For example:
 
 .. code-block:: rust
 
@@ -159,5 +144,5 @@ All bool, numeric and string Kconfig settings are accessible from the
 Other functionality
 -------------------
 
-Access to other functionality within zephyr is a work-in-progress, and
-this document will be updated as that is done.
+Access to other functionality within zephyr is a work-in-progress, and this document will be updated
+as that is done.