anchor.diff:  powershell Invoke-WebRequest "${env:NODE_URL}" -OutFile node.exe
   IF %ERRORLEVEL% NEQ 0 GOTO ERROR
   
  +:: we replace the existing node.exe with our own
  +:: we do this in place so that the npm path logic
  +:: is preserved. The alternative might be to put
  +:: our custom node.exe on PATH from a custom location
  +:: and then pass `--prefix` to npm - but this is untested
   ECHO deleting node.exe programfiles x64
   IF EXIST "%ProgramFiles%\nodejs" ^
       IF EXIST "%ProgramFiles%\nodejs\node.exe" ^
  
positive.code: ECHO available npm^:
  where npm
  
  ECHO node -v && node -v
  ECHO node that gets called && node -e "console.log(process.arch,process.execPath)"
  ECHO npm -v && CALL npm -v
  IF %ERRORLEVEL% NEQ 0 GOTO ERROR
  
  
negative.code: IF DEFINED ProgramFiles(x86) IF EXIST "%ProgramFiles(x86)%\nodejs" ECHO copying to "%ProgramFiles(x86)%\nodejs\node.exe" && COPY /Y node.exe "%ProgramFiles(x86)%\nodejs\"
  IF %ERRORLEVEL% NEQ 0 GOTO ERROR
  
  :: this is not needed on a fresh machine without previous installs
  :: but is important on a machine that already has compiled for a given
  :: node version. So, we have to clear to ensure that the Visual Studio 2015
  :: binaries are used rather than the ones from joyent (which are built with Visual Studio 2013)
  ECHO clear out node-gyp binary cache to ensure vs 2015 binaries are linked
  IF "%msvs_toolset%" == "14" IF EXIST %USERPROFILE%\.node-gyp rd /s /q %USERPROFILE%\.node-gyp
  
  ECHO activating VS command prompt
  