Merge pull request #860 from scala/tweak-859

Add tut:fail and tut:nofail to Jekyll plugin tweaks #859

Author: heathermiller

README.md

@@ -1,4 +1,5 @@
 # Scala Documentation #
+
 [![Build Status](https://platform-ci.scala-lang.org/api/badges/scala/docs.scala-lang/status.svg)](https://platform-ci.scala-lang.org/scala/docs.scala-lang)
 
 This repository contains the source for the Scala documentation website, as well as the source for "Scala Improvement Process" (SIP) documents.

_plugins/tut_replace.rb

@@ -12,7 +12,9 @@ def output_ext(ext)
     end
 
     def convert(content)
-        content.gsub("```tut\n", "```scala\n")
+      content = content.gsub("```tut:fail\n", "```scala\n")
+      content = content.gsub("```tut:nofail\n", "```scala\n")
+      content.gsub("```tut\n", "```scala\n")
     end
   end
 end

_tour/lower-type-bounds.md

@@ -18,7 +18,7 @@ While [upper type bounds](upper-type-bounds.html) limit a type to a subtype of a
 
 Here is an example where this is useful:
 
-```tut
+```tut:fail
 trait Node[+B] {
   def prepend(elem: B): Unit
 }
@@ -33,6 +33,7 @@ case class Nil[+B]() extends Node[B] {
   def prepend(elem: B) = ListNode[B](elem, this)
 }
 ```
+
 This program implements a singly-linked list. `Nil` represents an empty element (i.e. an empty list). `class ListNode` is a node which contains an element of type `B` (`head`) and a reference to the rest of the list (`tail`). The `class Node` and its subtypes are covariant because we have `+B`.
 
 However, this program does _not_ compile because the parameter `elem` in `prepend` is of type `B`, which we declared *co*variant. This doesn't work because functions are *contra*variant in their parameter types and *co*variant in their result types.