SYNTAX.md

Syntax of the SubTiger Language

Everything in SubTiger is actually an expression, and hence always evaluates to some value. Now, we may look at some sample code to understand the syntax better:

1. We can use a variable only after its declaration.
   We need to separate every expression using a ;.
   The print function is a built-in function that prints the integer expression's value after evaluating.
   The println function is also a built-in function that appends a newline also while printing.

   x := 5;
   y := 7;
   z := x * y;
   println (x + z);
   print (z / y);
   

2. For-loops are also expressions. Both the start and end positions are inclusive. There are two types of for-loops:

   • Without any step size (defaults to +1)

     for i := 0 to 10 do
         println i;
     done;
     

   • With step size mentioned

     x := 5;
     
     for i := 10 to 1 by -2 do
         x := i - 2;
         println x;
     done;
     
     println x;
     

Example Programs

Please refer to the example programs in the directory tests/