Has anyone else use this construct ?

[carlsomo]

It works it seems for dirty cmd line parrameters?

Code: Select all

if !"%~1" equ ""! goto :whatever

[Endoro]

This might be useful if you want to check if 1) %1 is empty AND 2) delayed expansion is on.

[trebor68]

I have tested the following codes.

Code: Select all

@echo off
setlocal enableextensions enabledelayedexpansion
echo.
echo  SETLOCAL with ENABLEDELAYEDEXPANSION
if !"%~1" equ ""! goto :whatever
echo.
echo First parameter: %1
goto :eof

:whatever
echo.
echo No parameter.

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@echo off
setlocal enableextensions disabledelayedexpansion
echo.
echo  SETLOCAL with DISABLEDELAYEDEXPANSION
if !"%~1" equ ""! goto :whatever
echo.
echo First parameter: %1
goto :eof

:whatever
echo.
echo No parameter.

Here the result of this codes:

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C:\Test2>test40

 SETLOCAL with ENABLEDELAYEDEXPANSION

No parameter.

C:\Test2>test40 Hallo Peggy Sue

 SETLOCAL with ENABLEDELAYEDEXPANSION

First parameter: Hallo

C:\Test2>test40

 SETLOCAL with DISABLEDELAYEDEXPANSION

First parameter:

C:\Test2>test40 Hallo Peggy Sue

 SETLOCAL with DISABLEDELAYEDEXPANSION

First parameter: Hallo

C:\Test2>

When use SETLOCAL DISABLEDELAYEDEXPANSION is the IF construct: IF !"" equ ""! goto :whatever when the parameter ist empty.

[Endoro]

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@ECHO OFF & setlocal disabledelayedexpansion
if !"%~1" equ ""! (echo equal) else echo not equal
setlocal enabledelayedexpansion
if !"%~1" equ ""! (echo equal) else echo not equal

Output without parameter is:

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not equal
equal

.. and with parameter:

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not equal
not equal

[Liviu]

It works it seems for dirty cmd line parrameters?

Define "dirty" and "work" Maybe you should clarify what exactly the code is attempting to do.

Output .. with parameter:

Except if the parameter is ^" or ^^ or other "dirty" variations.

Liviu