@INC[string] returns

 

1 if string is empty

otherwise the same value as @EVAL[string + 1]

 

If string is the name of an environment variable, its value is used whether or not it is preceded by a percent mark % without modifying the value of the variable. To actually increment the value of the variable var use

 

set var=%@inc[%var]

 

Example:

 

set start=5

set result=%inc[start]

echo %result

6