Exiting out of a FOR loop in a batch file?

Question

Why does this batch file never break out of the loop?

For /L %%f In (1,1,1000000) Do @If Not Exist %%f Goto :EOF 

Shouldn't the Goto :EOF break out of the loop?

Edit:

I guess I should've asked more explicitly... how can I break out of the loop?

Answer 1

You could simply use echo on and you will see that goto :eof or even exit /b doesn't work as expected.

The code inside of the loop isn't executed anymore, but the loop is expanded for all numbers to the end.
That's why it's so slow.

The only way to exit a FOR /L loop seems to be the variant of exit like the exsample of Wimmel, but this isn't very fast nor useful to access any results from the loop.

This shows 10 expansions, but none of them will be executed

echo on for /l %%n in (1,1,10) do (   goto :eof   echo %%n ) 

Answer 2

Based on Tim's second edit and this page you could do this:

@echo off if "%1"=="loop" (   for /l %%f in (1,1,1000000) do (     echo %%f     if exist %%f exit   )   goto :eof ) cmd /v:on /q /d /c "%0 loop" echo done 

This page suggests a way to use a goto inside a loop, it seems it does work, but it takes some time in a large loop. So internally it finishes the loop before the goto is executed.