diff --git a/src/_guides/language/language-tour.md b/src/_guides/language/language-tour.md
index adf284af25..19f6049cef 100644
--- a/src/_guides/language/language-tour.md
+++ b/src/_guides/language/language-tour.md
@@ -3,463 +3,471 @@ title: A tour of the Dart language
 description: A tour of all the major Dart language features.
 short-title: Language tour
 js: [{url: 'https://dartpad.dev/inject_embed.dart.js', defer: true}]
+sitemap: false
 ---
-<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
-
-
 
 ## A basic Dart program
 
-
+This content has moved to [Introduction to the Dart language](/language/basics).
 
 ## Important concepts
 
-
+This content has moved to [Introduction to the Dart language](/language/basics).
 
 ## Keywords
 
-
+This content has moved to [Keywords](/language/keywords).
 
 ## Variables
 
-
+This content has moved to [Variables](/language/variables).
 
 
 ### Default value
 
-
+This content has moved to [Variables](/language/variables#default-value).
 
 ### Late variables
 
-
+This content has moved to [Variables](/language/variables#late-variables).
 
 ### Final and const
 
 
-
+This content has moved to [Variables](/language/variables#final-and-const).
 
 ## Built-in types
 
-
+This content has moved to [Built-in types](/language/built-in-types).
 
 ### Numbers
 
-
+This content has moved to [Built-in types](/language/built-in-types#numbers).
 
 ### Strings
 
+This content has moved to [Built-in types](/language/built-in-types#strings).
 
 ### Booleans
 
-
+This content has moved to [Built-in types](/language/built-in-types#booleans).
 
 ### Lists
 
+This content has moved to [Collection types](/language/collection-types#lists).
 
 ### Sets
 
-
+This content has moved to [Collection types](/language/collection-types#sets).
 
 ### Maps
 
+This content has moved to [Collection types](/language/collection-types#maps).
 
 ### Runes and grapheme clusters
 
-
+This content has moved to [Built-in types](/language/built-in-types#runes-and-grapheme-clusters).
 
 ### Symbols
 
-
+This content has moved to [Built-in types](/language/built-in-types#symbols).
 
 ## Functions
 
-
+This content has moved to [Functions](/language/functions).
 
 ### Parameters
 
-
+This content has moved to [Functions](/language/functions#parameters).
 
 #### Named parameters
 
-
+This content has moved to [Functions](/language/functions#named-parameters).
 
 #### Optional positional parameters
 
+This content has moved to [Functions](/language/functions#optional-positional-parameters).
 
 ### The main() function
 
-
+This content has moved to [Functions](/language/functions#the-main-function).
 
 ### Functions as first-class objects
 
-
+This content has moved to [Functions](/language/functions#functions-as-first-class-objects).
 
 ### Anonymous functions
 
+This content has moved to [Functions](/language/functions#anonymous-functions).
 
 ### Lexical scope
 
-
-
+This content has moved to [Functions](/language/functions#lexical-scope).
 
 ### Lexical closures
 
-
+This content has moved to [Functions](/language/functions#lexical-closures).
 
 ### Testing functions for equality
 
+This content has moved to [Functions](/language/functions#testing-functions-for-inequality).
 
 ### Return values
 
-
-
+This content has moved to [Functions](/language/functions#return-values).
 
 ## Operators
 
+This content has moved to [Operators](/language/operators).
 
 ### Arithmetic operators
 
-
+This content has moved to [Operators](/language/operators#arithmetic-operators).
 
 ### Equality and relational operators
 
+This content has moved to [Operators](/language/operators#equality-and-relational-operators).
 
 ### Type test operators
 
-
+This content has moved to [Operators](/language/operators#type-test-operators).
 
 ### Assignment operators
 
-
+This content has moved to [Operators](/language/operators#assignment-operators).
 
 ### Logical operators
 
-
+This content has moved to [Operators](/language/operators#logical-operators).
 
 ### Bitwise and shift operators
 
+This content has moved to [Operators](/language/operators#bitwise-and-shift-operators).
 
 ### Conditional expressions
 
+This content has moved to [Operators](/language/operators#conditional-operators).
 
 ### Cascade notation
 
-
+This content has moved to [Operators](/language/operators#cascade-notation).
 
 ### Other operators
 
-
-
+This content has moved to [Operators](/language/operators#other-operators).
 
 ## Control flow statements
 
-
-
+This content has moved to [Control flow](/language/control-flow).
 
 ### If and else
 
-
+This content has moved to [Control flow](/language/control-flow#if-and-else).
 
 ### For loops
 
-
+This content has moved to [Control flow](/language/control-flow#for-loops).
 
 ### While and do-while
 
+This content has moved to [Control flow](/language/control-flow#while-and-do-while).
 
 ### Break and continue
 
-
+This content has moved to [Control flow](/language/control-flow#break-and-continue).
 
 ### Switch and case
 
-
+This content has moved to [Control flow](/language/control-flow#switch-and-case).
 
 ### Assert
 
+This content has moved to [Control flow](/language/control-flow#assert).
 
 ## Exceptions
 
-
+This content has moved to [Error handling](/language/error-handling#exceptions).
 
 ### Throw
 
-
+This content has moved to [Error handling](/language/error-handling#throw).
 
 ### Catch
 
-
+This content has moved to [Error handling](/language/error-handling#catch).
 
 ### Finally
 
-
+This content has moved to [Error handling](/language/error-handling#finally).
 
 ## Classes
 
-
+This content has moved to [Classes](/language/classes).
 
 
 ### Using class members
 
-
+This content has moved to [Classes](/language/classes#using-class-members).
 
 
 ### Using constructors
 
-
+This content has moved to [Classes](/language/classes#using-constructors).
 
 ### Getting an object's type
 
-
-
+This content has moved to [Classes](/language/classes#getting-an-objects-type).
 
 ### Instance variables
 
+This content has moved to [Classes](/language/classes#instance-variables).
 
 ### Constructors
 
-
+This content has moved to [Constructors](/language/constructors).
 
 #### Initializing formal parameters
 
-
-
+This content has moved to [Constructors](/language/constructors#initializing-formal-parameters).
 
 #### Default constructors
 
-
+This content has moved to [Constructors](/language/constructors#default-constructors).
 
 #### Constructors aren’t inherited
 
+This content has moved to [Constructors](/language/constructors#constructors-arent-inherited).
 
 #### Named constructors
 
+This content has moved to [Constructors](/language/constructors#named-constructors).
 
 #### Invoking a non-default superclass constructor
 
-
+This content has moved to [Constructors](/language/constructors#invoking-a-non-default-superclass-constructor).
 
 <a name="super-parameters"></a>
+### Super parameters
 
-
+This content has moved to [Constructors](/language/constructors#super-parameters).
 
 
 #### Initializer list
 
-
+This content has moved to [Constructors](/language/constructors#initializer-list).
 
 
 #### Redirecting constructors
 
-
+This content has moved to [Constructors](/language/constructors#redirecting-constructors).
 
 
 #### Constant constructors
 
 
-
+This content has moved to [Constructors](/language/constructors#constant-constructors).
 
 #### Factory constructors
 
-
-
+This content has moved to [Constructors](/language/constructors#factory-constructors).
 
 ### Methods
 
-
+This content has moved to [Methods](/language/methods).
 
 #### Instance methods
 
-
+This content has moved to [Methods](/language/methods#instance-methods).
 
 #### Operators {#_operators}
 
-
+This content has moved to [Methods](/language/methods#operators).
 
 
 #### Getters and setters
 
-
+This content has moved to [Methods](/language/methods#getters-and-setters).
 
 #### Abstract methods
 
-
-
+This content has moved to [Methods](/language/methods#abstract-methods).
 
 ### Abstract classes
 
+This content has moved to [Classes](/language/classes#abstract-classes).
 
 <a id="interfaces"></a>
 ### Implicit interfaces
 
-
+This content has moved to [Classes](/language/classes#implicit-interfaces).
 
 ### Extending a class
 
-
+This content has moved to [Extend a class](/language/extend).
 
 <a name="overridable-operators"></a>
 
 #### Overriding members
 
-
+This content has moved to [Extend a class](/language/extend#overriding-members).
 
 #### noSuchMethod()
 
-
+This content has moved to [Extend a class](/language/extend#nosuchmethod).
 
 ### Extension methods
 
+This content has moved to [Extension methods](/language/extension-methods).
+
 
 <a id="enums"></a>
 ### Enumerated types
 
+This content has moved to [Enumerated types](/language/enum).
 
 #### Declaring simple enums
 
-
+This content has moved to [Enumerated types](/language/enum#declaring-simple-enums).
 
 #### Declaring enhanced enums
 
+This content has moved to [Enumerated types](/language/enum#declaring-enhanced-enums).
 
 #### Using enums
 
-
+This content has moved to [Enumerated types](/language/enum#using-enums).
 
 
 <a id="mixins"></a>
 ### Adding features to a class: mixins
 
+This content has moved to [Mixins](/language/mixins).
 
 ### Class variables and methods
 
+This content has moved to [Classes](/language/classes#class-variables-and-methods).
 
 #### Static variables
 
+This content has moved to [Classes](/language/classes#static-variables).
 
 #### Static methods
 
-
+This content has moved to [Classes](/language/classes#static-methods).
 
 ## Generics
 
-
+This content has moved to [Generics](/language/generics).
 
 ### Why use generics?
 
+This content has moved to [Generics](/language/generics#why-use-generics).
 
 ### Using collection literals
 
-
-
+This content has moved to [Generics](/language/generics#using-collection-literals).
 
 ### Using parameterized types with constructors
 
-
+This content has moved to [Generics](/language/generics#using-parameterized-types-with-constructors).
 
 ### Generic collections and the types they contain
 
-
-
+This content has moved to [Generics](/language/generics#generic-collections-and-the-types-they-contain).
 
 ### Restricting the parameterized type
 
-
-
+This content has moved to [Generics](/language/generics#restricting-the-parameterized-type).
 
 ### Using generic methods
 
-
-
+This content has moved to [Generics](/language/generics#using-generic-methods).
 
 ## Libraries and visibility
 
-
+This content has moved to [Libraries & visibility](/guides/libraries/visibility).
 
 ### Using libraries
 
-
+This content has moved to [Libraries & visibility](/guides/libraries/visibility#using-libraries).
 
 #### Specifying a library prefix
 
-
+This content has moved to [Libraries & visibility](/guides/libraries/visibility#specifying-a-library-prefix).
 
 #### Importing only part of a library
 
-
+This content has moved to [Libraries & visibility](/guides/libraries/visibility#importing-only-part-of-a-library).
 
 <a id="deferred-loading"></a>
 #### Lazily loading a library
 
+This content has moved to [Libraries & visibility](/guides/libraries/visibility#lazily-loading-a-library).
 
 #### The `library` directive {#library-directive}
 
+This content has moved to [Libraries & visibility](/guides/libraries/visibility#the-library-directive).
 
 ### Implementing libraries
 
-
+This content has moved to [Libraries & visibility](/guides/libraries/visibility#implementing-libraries).
 
 <a id="asynchrony"></a>
 ## Asynchrony support
 
-
+This content has moved to [Asynchrony support](/language/async).
 
 <a id="await"></a>
 ### Handling Futures
 
-
+This content has moved to [Asynchrony support](/language/async#handling-futures).
 
 <a id="async"></a>
 ### Declaring async functions
 
-
+This content has moved to [Asynchrony support](/language/async#declaring-async-functions).
 
 <a id="await-for"></a>
 ### Handling Streams
 
-
+This content has moved to [Asynchrony support](/language/async#handling-streams).
 
 <a id="generator"></a>
 ## Generators
 
-
+This content has moved to [Generators](/language/generators).
 
 ## Callable classes
 
-
+This content has moved to [Callable classes](/language/callable-classes).
 
 ## Isolates
 
-
+This content has moved to [Isolates](/language/concurrency).
 
 ## Typedefs
 
-
+This content has moved to [Typedefs](/language/typedefs).
 
 
 ## Metadata
 
-
+This content has moved to [Metadata](/language/metadata).
 
 
 ## Comments
 
-
+This content has moved to [Comments](/language/comments).
 
 ### Single-line comments
 
-
+This content has moved to [Comments](/language/comments#single-line-comments).
 
 
 ### Multi-line comments
 
-
+This content has moved to [Comments](/language/comments#multi-line-comments).
 
 ### Documentation comments
 
-
-
-
-## Summary
-
-
+This content has moved to [Comments](/language/comments#documentation-comments).
diff --git a/src/language/async.md b/src/language/async.md
index cb04bb318d..d6c33ae743 100644
--- a/src/language/async.md
+++ b/src/language/async.md
@@ -3,6 +3,8 @@ title: Asychrony support
 description: Information on writing asynchronous code in Dart.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 Dart libraries are full of functions that
 return [`Future`][] or [`Stream`][] objects.
 These functions are _asynchronous_:
diff --git a/src/language/classes.md b/src/language/classes.md
index 1196d5024e..befc3b5b3b 100644
--- a/src/language/classes.md
+++ b/src/language/classes.md
@@ -3,6 +3,8 @@ title: Classes
 description: Summary of classes, class instances, and their members.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 Dart is an object-oriented language with classes and mixin-based
 inheritance. Every object is an instance of a class, and all classes
 except `Null` descend from [`Object`][].
diff --git a/src/language/constructors.md b/src/language/constructors.md
index 6374b6c14e..03d391035c 100644
--- a/src/language/constructors.md
+++ b/src/language/constructors.md
@@ -3,6 +3,8 @@ title: Constructors
 description: Everything about using constructors in Dart.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 Declare a constructor by creating a function with the same name as its
 class (plus, optionally, an additional identifier as described in
 [Named constructors](#named-constructors)).
diff --git a/src/language/generics.md b/src/language/generics.md
index 32d1bcc5c6..5ded6d4d50 100644
--- a/src/language/generics.md
+++ b/src/language/generics.md
@@ -3,6 +3,8 @@ title: Generics
 description: Learn about generic types in Dart.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 If you look at the API documentation for the basic array type,
 [`List`][], you’ll see that the
 type is actually `List<E>`. The \<...\> notation marks List as a
diff --git a/src/language/mixins.md b/src/language/mixins.md
index c4ee89cc56..c924bbda70 100644
--- a/src/language/mixins.md
+++ b/src/language/mixins.md
@@ -3,6 +3,8 @@ title: Mixins
 description: Learn how to add to features to a class in Dart.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 Mixins are a way of reusing a class's code in multiple class
 hierarchies.
 
diff --git a/src/language/operators.md b/src/language/operators.md
index 33681edc60..24f865b4fb 100644
--- a/src/language/operators.md
+++ b/src/language/operators.md
@@ -3,6 +3,8 @@ title: Operators
 description: Learn about the operators Dart supports.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 <a name="operators"></a>
 
 Dart supports the operators shown in the following table.
diff --git a/src/language/typedefs.md b/src/language/typedefs.md
index efb0234ac6..1bbcf5cdc8 100644
--- a/src/language/typedefs.md
+++ b/src/language/typedefs.md
@@ -3,6 +3,8 @@ title: Typedefs
 description: Learn about type aliases in Dart.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 A type alias—often called a _typedef_ because
 it's declared with the keyword `typedef`—is
 a concise way to refer to a type.
diff --git a/src/language/variables.md b/src/language/variables.md
index 333dda6500..e913b8c09c 100644
--- a/src/language/variables.md
+++ b/src/language/variables.md
@@ -3,6 +3,8 @@ title: Variables
 description: Learn about variables in Dart.
 ---
 
+<?code-excerpt replace="/ *\/\/\s+ignore_for_file:[^\n]+\n//g; /(^|\n) *\/\/\s+ignore:[^\n]+\n/$1/g; /(\n[^\n]+) *\/\/\s+ignore:[^\n]+\n/$1\n/g; / *\/\/\s+ignore:[^\n]+//g; /([A-Z]\w*)\d\b/$1/g"?>
+
 Here’s an example of creating a variable and initializing it:
 
 <?code-excerpt "misc/lib/language_tour/variables.dart (var-decl)"?>