Batch FOR loop IF and SET conflict - batch-file

Question

So, I was writing a small batch-file game, and came across this problem in the FOR loop.
This is a small chunk of my code.
If the player picks-up the rock, check if it is on the table, then put it in your pack.
The problem is the SET command doesn't work.
I guess that lines executes as : set %table1%=empty not : set table1=empty.
I feel like there is a simple solution to this problem, I've trying for a few days in my spare time, but haven't gotten it.
Any help is appreciated!
set take=rock
set table1=box
set table2=rock
set table3=wrench
for %%x in (%table1% %table2% %table3%) do (
if %%x==%take% (
set %%x=empty
set pack=%%x
goto tableRoom
)
)

Answer 1

The main problem with your code is set %%x=empty for a logical reason: the for loop is iterating over the list of the values inside the table variables, not over the name of the variables so you can not change the value of the variable when you don't have a reference to the variable, you have the value inside it.
Enabling delayed expansion and iterating over the names of the variables can solve the problem
#echo off
setlocal enableextensions enabledelayedexpansion
set "take=rock"
set "table1=box"
set "table2=rock"
set "table3=wrench"
for %%x in (table1 table2 table3) do (
if "!%%x!"=="%take%" (
set "%%x=empty"
set "pack=%take%"
goto tableRoom
)
)
:tableRoom
set table
exit /b
%%x will hold the name of the variable, so when !%%x! is executed it will be something like !table1!, retrieving the value inside the variable (when delayed expansion is enabled).
If the names of the used variables (table...) does not collide with anything else, and you don't want to use delayed expansion, it is possible to take the output of set table command (the list the variables with its values) and process this list with a for /f command, splitting the command output, separating variable name and value
#echo off
setlocal enableextensions disabledelayedexpansion
set "take=rock"
set "table1=box"
set "table2=rock"
set "table3=wrench"
for /f "tokens=1,* delims==" %%a in ('set table') do (
if "%%b"=="%take%" (
set "%%a=empty"
set "pack=%take%"
goto tableRoom
)
)
:tableRoom
set table
exit /b
The output of set command contains var=value. Each of the lines is splitted using the = as a delimiter to get two tokens (tokens=1,*). %%a will hold the first token (the variable name) and %%b the rest of the line (the value in the variable)

Answer 2

You can use a counter to now which table you're testing in your FOR loop and
set directly the table!N! as empty :
set take=rock
set table1=box
set table2=rock
set table3=wrench
setlocal enabledelayedexpansion
set $c=1
for %%x in (%table1% %table2% %table3%) do (
if %%x==%take% (
set table!$c!=empty
set pack=%%x
goto tableRoom
)
set /a $c+=1
)
:tableroom
echo table2 is now : %table2%