Hacked in Math Lexer

lib/banzai/filter/syntax_highlight_filter.rb

 require 'rouge/plugins/redcarpet'
 
+module Rouge
+  module Lexers
+    class Math < Lexer
+      title "Plain Text"
+      desc "A boring lexer that doesn't highlight anything"
+
+      tag 'math'
+      aliases 'text'
+      filenames '*.txt'
+      mimetypes 'text/plain'
+
+      default_options :token => 'Text'
+
+      def token
+        @token ||= Token[option :token]
+      end
+
+      def stream_tokens(string, &b)
+        yield self.token, string
+      end
+    end
+  end
+end
+
 module Banzai
   module Filter
     # HTML Filter to highlight fenced code blocks
@@ -48,6 +72,9 @@ module Banzai
       end
 
       def lexer_for(language)
+        if language == 'math'
+          return Rouge::Lexers::Math.new
+        end
         (Rouge::Lexer.find(language) || Rouge::Lexers::PlainText).new
       end