Fix the executable load error under 1.9.2.

Closes gh-309

doc-src/HAML_CHANGELOG.md

@@ -3,6 +3,10 @@
 * Table of contents
 {:toc}
 
+## 3.0.23 (Unreleased)
+
+* Fix the error message for unloadable modules when running the executables under Ruby 1.9.2.
+
 ## 3.0.22
 
 [Tagged on GitHub](http://github.com/nex3/haml/commit/3.0.22).

doc-src/SASS_CHANGELOG.md

@@ -3,6 +3,10 @@
 * Table of contents
 {:toc}
 
+## 3.0.23 (Unreleased)
+
+* Fix the error message for unloadable modules when running the executables under Ruby 1.9.2.
+
 ## 3.0.22
 
 [Tagged on GitHub](http://github.com/nex3/haml/commit/3.0.22).

lib/haml/exec.rb

@@ -155,7 +155,7 @@ module Haml
       end
 
       def handle_load_error(err)
-        dep = err.message.scan(/^no such file to load -- (.*)/)[0]
+        dep = err.message[/^no such file to load -- (.*)/, 1]
         raise err if @options[:trace] || dep.nil? || dep.empty?
         $stderr.puts <<MESSAGE
 Required dependency #{dep} not found!