Add header insert/append docs

Adds docs for inserting / appending to:
- Request
- Response
- Trailers

Author: yoshuawuyts

src/request.rs

@@ -213,6 +213,19 @@ impl Request {
     }
 
     /// Set an HTTP header.
+    /// 
+    /// # Examples
+    ///
+    /// ```
+    /// # fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync + 'static>> {
+    /// #
+    /// use http_types::{Url, Method, Request};
+    ///
+    /// let mut req = Request::new(Method::Get, Url::parse("https://example.com")?);
+    /// req.insert_header("Content-Type", "text/plain")?;
+    /// #
+    /// # Ok(()) }
+    /// ```
     pub fn insert_header(
         &mut self,
         name: impl TryInto<HeaderName>,
@@ -225,6 +238,19 @@ impl Request {
     ///
     /// Unlike `insert` this function will not override the contents of a header, but insert a
     /// header if there aren't any. Or else append to the existing list of headers.
+    /// 
+    /// # Examples
+    ///
+    /// ```
+    /// # fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync + 'static>> {
+    /// #
+    /// use http_types::{Url, Method, Request};
+    ///
+    /// let mut req = Request::new(Method::Get, Url::parse("https://example.com")?);
+    /// req.append_header("Content-Type", "text/plain")?;
+    /// #
+    /// # Ok(()) }
+    /// ```
     pub fn append_header(
         &mut self,
         name: impl TryInto<HeaderName>,

src/response.rs

@@ -21,10 +21,10 @@ pin_project_lite::pin_project! {
     /// ```
     /// # fn main() -> Result<(), http_types::url::ParseError> {
     /// #
-    /// use http_types::{Url, Method, Request};
+    /// use http_types::{Response, StatusCode};
     ///
-    /// let mut req = Request::new(Method::Get, Url::parse("https://example.com")?);
-    /// req.set_body("Hello, Nori!");
+    /// let mut res = Response::new(StatusCode::Ok);
+    /// res.set_body("Hello, Nori!");
     /// #
     /// # Ok(()) }
     /// ```
@@ -75,6 +75,19 @@ impl Response {
     }
 
     /// Set an HTTP header.
+    /// 
+    /// # Examples
+    ///
+    /// ```
+    /// # fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync + 'static>> {
+    /// #
+    /// use http_types::{Url, Method, Request};
+    ///
+    /// let mut req = Request::new(Method::Get, Url::parse("https://example.com")?);
+    /// req.insert_header("Content-Type", "text/plain")?;
+    /// #
+    /// # Ok(()) }
+    /// ```
     pub fn insert_header(
         &mut self,
         name: impl TryInto<HeaderName>,
@@ -87,6 +100,19 @@ impl Response {
     ///
     /// Unlike `insert` this function will not override the contents of a header, but insert a
     /// header if there aren't any. Or else append to the existing list of headers.
+    /// 
+    /// # Examples
+    ///
+    /// ```
+    /// # fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync + 'static>> {
+    /// #
+    /// use http_types::{Response, StatusCode};
+    ///
+    /// let mut res = Response::new(StatusCode::Ok);
+    /// res.append_header("Content-Type", "text/plain")?;
+    /// #
+    /// # Ok(()) }
+    /// ```
     pub fn append_header(
         &mut self,
         name: impl TryInto<HeaderName>,
@@ -102,10 +128,10 @@ impl Response {
     /// ```
     /// # fn main() -> Result<(), http_types::url::ParseError> {
     /// #
-    /// use http_types::{Url, Method, Request};
+    /// use http_types::{Response, StatusCode};
     ///
-    /// let mut req = Request::new(Method::Get, Url::parse("https://example.com")?);
-    /// req.set_body("Hello, Nori!");
+    /// let mut res = Response::new(StatusCode::Ok);
+    /// res.set_body("Hello, Nori!");
     /// #
     /// # Ok(()) }
     /// ```

src/trailers.rs

@@ -70,6 +70,19 @@ impl Trailers {
     }
 
     /// Insert a header into the headers.
+    /// 
+    /// # Examples
+    ///
+    /// ```
+    /// # fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync + 'static>> {
+    /// #
+    /// use http_types::Trailers;
+    ///
+    /// let mut trailers = Trailers::new();
+    /// trailers.insert("Content-Type", "text/plain")?;
+    /// #
+    /// # Ok(()) }
+    /// ```
     pub fn insert(
         &mut self,
         name: impl TryInto<HeaderName>,
@@ -82,6 +95,19 @@ impl Trailers {
     ///
     /// Unlike `insert` this function will not override the contents of a header, but insert a
     /// header if there aren't any. Or else append to the existing list of headers.
+    /// 
+    /// # Examples
+    ///
+    /// ```
+    /// # fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync + 'static>> {
+    /// #
+    /// use http_types::Trailers;
+    ///
+    /// let mut trailers = Trailers::new();
+    /// trailers.append("Content-Type", "text/plain")?;
+    /// #
+    /// # Ok(()) }
+    /// ```
     pub fn append(&mut self, name: impl TryInto<HeaderName>, values: impl ToHeaderValues) -> io::Result<()> {
         self.headers.append(name, values)
     }