diff --git a/src/header/common/accept.rs b/src/header/common/accept.rs
index 84a1d800..b0dca445 100644
--- a/src/header/common/accept.rs
+++ b/src/header/common/accept.rs
@@ -34,6 +34,7 @@ header! {
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::{Accept, qitem};
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     ///
     /// builder.set(
@@ -41,6 +42,7 @@ header! {
     ///         qitem(mime::TEXT_HTML),
     ///     ])
     /// );
+    /// # }
     /// ```
     ///
     /// ```rust
@@ -49,6 +51,7 @@ header! {
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::{Accept, qitem};
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     ///
     /// builder.set(
@@ -56,6 +59,7 @@ header! {
     ///         qitem(mime::APPLICATION_JSON),
     ///     ])
     /// );
+    /// # }
     /// ```
     ///
     /// ```rust
@@ -64,6 +68,7 @@ header! {
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::{Accept, QualityItem, q, qitem};
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     ///
     /// builder.set(
@@ -81,6 +86,7 @@ header! {
     ///         ),
     ///     ])
     /// );
+    /// # }
     /// ```
     (Accept, http::ACCEPT) => (QualityItem<Mime>)+
 
diff --git a/src/header/common/accept_charset.rs b/src/header/common/accept_charset.rs
index 781445de..1e798ad6 100644
--- a/src/header/common/accept_charset.rs
+++ b/src/header/common/accept_charset.rs
@@ -26,16 +26,19 @@ header! {
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::{AcceptCharset, Charset, qitem};
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// builder.set(
     ///     AcceptCharset(vec![qitem(Charset::Us_Ascii)])
     /// );
+    /// # }
     /// ```
     /// ```rust
     /// # extern crate actix_web;
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::{AcceptCharset, Charset, q, QualityItem};
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// builder.set(
     ///     AcceptCharset(vec![
@@ -43,16 +46,19 @@ header! {
     ///         QualityItem::new(Charset::Iso_8859_10, q(200)),
     ///     ])
     /// );
+    /// # }
     /// ```
     /// ```rust
     /// # extern crate actix_web;
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::{AcceptCharset, Charset, qitem};
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// builder.set(
     ///     AcceptCharset(vec![qitem(Charset::Ext("utf-8".to_owned()))])
     /// );
+    /// # }
     /// ```
     (AcceptCharset, http::ACCEPT_CHARSET) => (QualityItem<Charset>)+
 
diff --git a/src/header/common/accept_language.rs b/src/header/common/accept_language.rs
index 916181b4..a2486c60 100644
--- a/src/header/common/accept_language.rs
+++ b/src/header/common/accept_language.rs
@@ -29,6 +29,7 @@ header! {
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::{AcceptLanguage, LanguageTag, qitem};
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// let mut langtag: LanguageTag = Default::default();
     /// langtag.language = Some("en".to_owned());
@@ -38,6 +39,7 @@ header! {
     ///         qitem(langtag),
     ///     ])
     /// );
+    /// # }
     /// ```
     ///
     /// ```rust
diff --git a/src/header/common/allow.rs b/src/header/common/allow.rs
index 274c691f..87c02897 100644
--- a/src/header/common/allow.rs
+++ b/src/header/common/allow.rs
@@ -29,10 +29,12 @@ header! {
     /// use actix_web::header::Allow;
     /// use http::Method;
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// builder.set(
     ///     Allow(vec![Method::GET])
     /// );
+    /// # }
     /// ```
     ///
     /// ```rust
@@ -42,6 +44,7 @@ header! {
     /// use actix_web::header::Allow;
     /// use http::Method;
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// builder.set(
     ///     Allow(vec![
@@ -50,6 +53,7 @@ header! {
     ///         Method::PATCH,
     ///     ])
     /// );
+    /// # }
     /// ```
     (Allow, http::ALLOW) => (Method)*
 
diff --git a/src/header/common/content_type.rs b/src/header/common/content_type.rs
index 730bbd94..c2e1bad0 100644
--- a/src/header/common/content_type.rs
+++ b/src/header/common/content_type.rs
@@ -35,23 +35,27 @@ header! {
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::ContentType;
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// builder.set(
     ///     ContentType::json()
     /// );
+    /// # }
     /// ```
     ///
     /// ```rust
     /// # extern crate mime;
     /// # extern crate actix_web;
-    /// use mime;
+    /// use mime::TEXT_HTML;
     /// use actix_web::httpcodes::HttpOk;
     /// use actix_web::header::ContentType;
     ///
+    /// # fn main() {
     /// let mut builder = HttpOk.build();
     /// builder.set(
-    ///     ContentType(mime::TEXT_HTML)
+    ///     ContentType(TEXT_HTML)
     /// );
+    /// # }
     /// ```
     (ContentType, http::CONTENT_TYPE) => [Mime]