Question

Since batch doesn’t really have ints, I have to work around it with set /a. Here I have a code segment (from a batch) that evaluates a numeric expression and sets it into a string:

@echo off
set test=|set /a 12-10
pause

My problem is that this actually prints the “test” string. This is quite inconvenient because I may need to change the string later. Is there any way around this (besides a whole bunch of cls)?

Answer 1

I believe

set /a test=12-10 > NUL

is what you’re after – your version doesn’t set test at all.

C:\temp>type t.cmd
@echo off
set /a test=1+5-21 > NUL
echo Test is: %test%

C:\temp>t.cmd
Test is: -15

You can even do indirect assignments like that:

C:\temp>type t.cmd
@echo off
setlocal
echo before: %mything%
set var=mything
set /a %var%=4+3
echo after: %mything%


C:\temp>t.cmd
before:
after: 7