flag_exists.cmd to flag_exec.cmd, also to lib as an option

vendor/lib/lib_profile.cmd

@@ -44,3 +44,134 @@ exit /b
   )
   popd
   exit /b
+
+:flag_exec
+  @echo off
+  setlocal
+  
+  if "%~1" equ "" call :wrongSyntax
+  
+  if not defined CMDER_USER_FLAGS (
+    :: in case nothing was passed to %CMDER_USER_FLAGS%
+    set "CMDER_USER_FLAGS= "
+  )
+  
+  set "feNot=false"
+  goto :parseArgument
+  
+  :doShift
+    shift
+  
+  :parseArgument
+  set "currenArgu=%~1"
+  if /i "%currenArgu%" equ "/setPath" (
+    :: set %flag_exists% shortcut
+    endlocal
+    set "flag_exists=%~dp0flag_exists"
+  ) else if /i "%currenArgu%" == "/?" (
+    call :help
+  ) else if /i "%currenArgu%" equ "/help" (
+    call :help
+  ) else if /i "%currenArgu%" equ "/h" (
+    call :help
+  ) else if /i "%currenArgu%" equ "NOT" (
+    set "feNot=true"
+    goto :doShift
+  ) else (
+    if "%~1" equ "" call :wrongSyntax
+    if "%~2" equ "" call :wrongSyntax
+    set "feFlagName=%~1"
+    set "feCommand=%~2"
+    if not "%~3" equ "" (
+      set "feParam=%~3"
+    )
+  )
+  
+  :: to avoid erroneous deteciton like "/do" "/doNOT", which both have a "/do"
+  :: we added a space after the flag name, like "/do ", which won't match "/doN"
+  set "feFlagName=%feFlagName% "
+  :: echo.
+  :: echo %CMDER_USER_FLAGS%
+  :: echo %feNOT%
+  :: echo %feFlagName%
+  :: echo %feCommand%
+  :: echo %feParam%
+  :: echo.
+  echo %CMDER_USER_FLAGS% | find /i "%feFlagName%">nul
+  if "%ERRORLEVEL%" == "0" (
+    if "%feNOT%" == "false" (
+      call %feCommand% %feParam%
+    )
+  ) else (
+    if "%feNOT%" == "true" (
+      call %feCommand% %feParam%
+    )
+  )
+  endlocal
+  exit /b
+  
+  :wrongSyntax
+  echo The syntax of the command is incorrect.
+  echo.
+  echo use /? for help
+  echo.
+  endlocal
+  exit /b
+  
+  :help
+  echo.
+  echo %%flag_exists%%
+  echo.
+  echo Handles with custom arguments for cmder's init.bat.
+  echo   written by xiazeyu, inspired DRSDavidSoft.
+  echo.
+  echo Usage:
+  echo.
+  echo %%flag_exists%% [/setPath] [NOT] flagName command/program [parameters]
+  echo.
+  echo   setPath          Generate a global varible %%flag_exists%% for
+  echo                    quicker use. Following arguments will be ignored.
+  echo.
+  echo   NOT              Specifies that %%flag_exists%% should carry out
+  echo                    the command only if the flag is missing.
+  echo.
+  echo   flagName         Specifies which flag name is to detect. It's recommand
+  echo                    to use a pair of double quotation marks to wrap
+  echo                    your flag name to avoid exceed expectation.
+  echo.
+  echo   command/program  Specifies the command to carry out if the
+  echo                    argument name is detected. It's recommand to
+  echo                    use a pair of double quotation marks to
+  echo                    wrap your command to avoid exceed expectation.
+  echo.
+  echo   parameters       These are the parameters passed to the command/program.
+  echo                    It's recommand to use a pair of double quotation marks 
+  echo                    to wrap your flag name to avoid exceed expectation.
+  echo.
+  echo Examples:
+  echo.
+  echo   these examples are expected to be writted in /config/user-profile.cmd
+  echo   it will use the environment varible "CMDER_USER_FLAGS"
+  echo.
+  echo   Case 1:
+  echo.
+  echo   The following command in user-profile.cmd would execute "notepad.exe"
+  echo.
+  echo     call %%flag_exists%% "/startNotepad" "start" "notepad.exe"
+  echo.
+  echo   if you pass parameter to init.bat like:
+  echo.
+  echo     init.bat /startNotepad
+  echo.
+  echo   Case 2:
+  echo.
+  echo   The following command in user-profile.cmd would execute "notepad.exe"
+  echo.
+  echo     call %%flag_exists%% NOT "/dontStartNotepad" "start" "notepad.exe"
+  echo.
+  echo   UNLESS you pass parameter to init.bat like:
+  echo.
+  echo     init.bat /dontStartNotepad
+  echo.
+  endlocal
+  exit /b