From: jj4public@gmail.com   
      
   On Sun, 7 Mar 2021 09:28:16 -0500, Tom Del Rosso wrote:   
   >   
   > But this doesn't explain (it seems to me) why the variable without   
   > percents has a different result. SET/A is supposed to behave the same   
   > with or without the percents.   
      
   With below command...   
      
     set /a y=%x%   
      
   The reason why it causes an error is because CMD performs syntax check then   
   expands any expandable variable references (which uses the percent sign),   
   THEN it executes the command.   
      
   So, if x variable contain 09, the command line would be like below before   
   it's executed.   
      
     set /a y=09   
      
   Meaning, the given value is a constant, rather than a variable name, from   
   the perspective of the SET /A command.   
      
   --- SoupGate-Win32 v1.05   
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