anchor.diff:              $dir = (Split-Path $_.FullName -Parent)
               $xml = [xml](Get-Content $_.FullName)
               foreach($li in $xml.make.generate.li){
  +                if( -not $li ){ continue }
                   foreach($target in $xml.make.generate.li.target){
  +                    if( -not $target ){ continue }
                       $path = (Join-Path $dir $target)
                       if( Test-Path $path ){
                           Do-Remove $path
  
positive.code: }
  
  function Newer-Than($source,$target){
      if( -not (Test-Path $target) ){
          Write-Verbose ("{0} not found." -f $target)
          return $true
  
negative.code:         $xml = [xml](Get-Content $_.FullName)
          :allloop foreach( $li in $xml.make.generate.li ){
              foreach( $target in $li.target ){
                  if( -not $target ){ continue }
                  foreach( $source in $li.source ){
                      if( -not $source ){ continue }
                      if( (Newer-Than $source $target) ){
                          Write-Verbose ("$ go generate for {0}" -f
                              (Join-Path $dir $target) )
                          go generate
  