anchor.diff:  }
   ----
   
  -Collapsing of code block is supported with `collapse` option
  -
  -[listing]
  -....
  -[source,java,title="Some unimportant or lengthy code hidden by default",collapse=true]
  -----
  -public class MyCode  {
  -    // long code block that should not be visible by default
  -}
  -----
  -....
  -
  -[source,java,title="Some unimportant or lengthy code hidden by default",collapse=true]
  -----
  -public class MyCode  {
  -    // long code block that should not be visible by default
  -}
  -----
   
   == Source Blocks from External Files (Full Content)
   
  
positive.code: 
  == Line Numbers
  
  Line numbers for source code blocks can be enabled either using the `:source-linenums-option:` attribute globally for
  all source blocks on the page, or per source block using the `linenums` option:
  
  [listing]
  
negative.code: ----
  
  
  == Collapsed Source Blocks
  
  Collapsing of source blocks is supported via the custom `collapse` option:
  
  [listing]
  ....
  [source,java,title="Collapsed Source Block",collapse=true]
  ----
  public class MyCode  {
      // long source block that should not be visible by default
  }
  ----
  ....
  
  [source,java,title="Collapsed Source Block",collapse=true]
  ----
  public class MyCode  {
      // long source block that should not be visible by default
  }
  ----
  
  
  == Source Highlighting
  
  AsciiDoc source highlighters (e.g. CodeRay) are not supported, in favor of using the source highlighting
  