anchor.diff:          wrapProgram $out/libexec/git-core/git-send-email \
                        --set GITPERLLIB "$gitperllib" ''
          else '' # replace git-send-email by notification script
  -        notSupported $out/libexec/git-core/git-send-email "reinstall with config git = { sendEmailSupport = true } set"
  +        notSupported $out/libexec/git-core/git-send-email
          '')
   
      + stdenv.lib.optionalString withManual ''# Install man pages and Info manual
  
positive.code:   postInstall =
      ''
        notSupported() {
          echo -e "#\!/bin/sh\necho '`basename $1` not supported, $2'\nexit 1" > "$1"
          chmod +x $1
        }
  
        # Install git-subtree.
  
negative.code:                      --set GITPERLLIB "$gitperllib"   \
                       --prefix PATH : "${svn}/bin" ''
         else '' # replace git-svn by notification script
          notSupported $out/libexec/git-core/git-svn
         '')
  
     + (if sendEmailSupport then
  