anchor.diff:  /// Support routines for primer design scenarios and primer generation for stitches
   open commonTypes
   open System
  -open System.Text
   open constants // primer parameters
   open Amyris.Bio.primercore
   open Amyris.Bio
  
positive.code:                      align = ANCHOR.LEFT;
                       strand = STRAND.TOP;
                       offset = 0;
                       targetTemp = dp.seamlessTm;
                       sequencePenalties = None}
                  //primercore.oligoDesign false pen task
                  pdWrap false pen task
  
          /// Called on success at finding fwd and reverse primers that can amplify the adjacent regions
  
negative.code:                     align = ANCHOR.CENTERLEFT;
                      strand = STRAND.TOP;
                      offset = 0;
                      targetTemp = dp.targetTm; // was historically seamlessTm incorrectly till ~ 10/2017
                      sequencePenalties = None}
  
                  pdWrap false pen task
  
              else
  