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Bring back the Compat layer

...And I thought I was going to have a good weekend.
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commit 14674883baf282913d2018c3f2c95a6f39d4851b 1 parent 39c540f
Vicent Marti vmg authored
Showing with 49 additions and 0 deletions.
  1. +28 −0 README.markdown
  2. +21 −0 lib/redcarpet/compat.rb
28 README.markdown
@@ -283,6 +283,34 @@ SmartyPants works on top of already-rendered HTML, and will ignore replacements
inside the content of HTML tags and inside specific HTML blocks such as
`<code>` or `<pre>`.
+What? You really want to mix Markdown renderers?
+What a terrible idea! Markdown is already ill-specified enough; if you create
+software that is renderer-independent, the results will be completely unreliable!
+Each renderer has its own API and its own set of extensions: you should choose one
+(it doesn't have to be Redcarpet, though that would be great!), write your
+software accordingly, and force your users to install it. That's the
+only way to have reliable and predictable Markdown output on your program.
+Still, if major forces (let's say, tornadoes or other natural disasters) force you
+to keep a Markdown-compatibility later, Redcarpet also supports this:
+ require 'redcarpet/compat'
+Requiring the compatibility library will declare a `Markdown` class with the
+classical RedCloth API, e.g.
+'this is my text').to_html
+This class renders 100% standards compliant Markdown with 0 extensions. Nada.
+Don't even try to enable extensions with a compatibility layer, because
+that's a maintance nightmare and won't work.
+On a related topic: if your Markdown gem has a `lib/markdown.rb` file that
+monkeypatches the Markdown class, you're a terrible human being. Just saying.
Boring legal stuff
21 lib/redcarpet/compat.rb
@@ -0,0 +1,21 @@
+require 'redcarpet'
+# Compatibility class;
+# Creates a instance of Redcarpet with the RedCloth
+# API. This instance has no extensions enabled whatsoever,
+# and no accessors to change this. 100% pure, standard
+# Markdown.
+class RedcarpetCompat
+ attr_accessor :text
+ def initialize(text, *_dummy)
+ @text = text
+ @markdown =
+ end
+ def to_html(*_dummy)
+ @markdown.render(@text)
+ end
+Markdown = RedcarpetCompat unless defined? Markdown
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