From: foxidrive@server.invalid   
      
   On 10.10.2016 08:33, Jean-Pierre Coulon wrote:   
   >> why can't I change a variable ? If I type set/a mavar=some expression   
   before,   
   >> the result comes at each ECHO line.   
   >>   
   >> for /L %%a in (1, 1, 5) do (   
   >> (set /a myvar="2*%%a+1")   
   >> echo %myvar%)   
      
      
    > Type  "set /?"  for am explanation and what to do.   
      
      
   I'll add some breadcrumbs here.  Hansel and Gretel would appreciate it.   
      
      
   @echo off   
   for /L %%a in (1, 1, 5) do (set /a myvar="2*%%a+1" & call echo %%myvar%%)   
   pause   
   for /L %%a in (1, 1, 5) do (set /a myvar="2*%%a+1" & echo "%myvar%")   
   pause   
   for /L %%a in (1, 1, 5) do (set /a myvar="2*%%a+1" & call echo %%myvar%%)   
   pause   
   setlocal enabledelayedexpansion   
   for /L %%a in (1, 1, 5) do (set /a myvar="2*%%a+1" & echo !myvar!)   
   pause   
      
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