anchor.diff:  open Microsoft.FSharp.Compiler
   open Microsoft.FSharp.Compiler.SourceCodeServices
   open FSharp.CompilerBinding
  +open ExtCore.Control
   
   module FSharpSyntaxModeInternals =
       let contains predicate sequence =
  
positive.code:         if doc <> null && doc.Project <> null then Some doc.Project else
          let view = doc.Annotation<MonoDevelop.SourceEditor.SourceEditorView>()
          if view <> null && view.Project <> null then Some view.Project
          else IdeApp.Workspace.GetProjectsContainingFile(doc.FileName.ToString()) |> Seq.tryHead
  
      let project = getProject document
  
  
negative.code:             let extraColorInfo =
                  maybe { let! document = Option.ofNull document
                          let! parsedDocument = Option.ofNull document.ParsedDocument
                          let! pc = Option.tryCast<ParseAndCheckResults> document.ParsedDocument.Ast
                          return! pc.GetExtraColorizations() }
  
              match (this.Document, line, offset, length, style) with
  