[Batch] Detect SetLocal DelayedExpansion or EnableExtensions support.

Example_DelayedExpansion.bat

:: Detect if Delayed Expansion or Command Extensions is supported.
:: Identify if delayed expansion is supported and handle both scenarios.
:: by David Ruhmann

:: Hide Commands
@echo off

rem setlocal /?
rem VERIFY OTHER 2>nul
rem SETLOCAL ENABLEEXTENSIONS
rem IF ERRORLEVEL 1 echo Unable to enable extensions
:: The same method can be applied to both Delayed Expansion and Command Extensions.
:: However, unless you expect your batch script to be run on Win95 or older systems
:: there should not be a worry about Command Extensions which, by default, are
:: enabled on Windows.  Delayed Expansion is another beast which should be checked.

:: Isolate Scope and Force Set Commands to Update upon Execution
verify other 2>nul
setlocal EnableDelayedExpansion
if ErrorLevel 0 goto DExEnabled
echo.ERROR: Unable to enable delayed expansion.
goto End
:DExEnabled


:: EXECUTE CODE HERE WHICH REQUIRES DELAYED EXPANSION.
echo.Delayed Expansion is enabled.


:End
endlocal
:: by David Ruhmann


:: ALTERNATE USAGE
:: Isolate Scope and Force Set Commands to Update upon Execution
set "xDExEnabled=false"
verify other 2>nul
setlocal EnableDelayedExpansion
if ErrorLevel 0 set "xDExEnabled=true"


:: Utilize Check
if /i "%xDExEnabled%"=="true"  rem EXECUTE CODE HERE WHICH REQUIRES DELAYED EXPANSION.
if /i "%xDExEnabled%"=="false" rem EXECUTE CODE HERE WHICH DOES NOT REQUIRE DELAYED EXPANSION.


endlocal
pause
:: by David Ruhmann

is
if errorlevel 0
correct? Doesn't this mean 'if errorlevel is 0 or greater than 0' which is therefore always true?
Shouldn't it be
if %errorlevel%==0
or
if not errorlevel 1