WLPP Programming Language Tutorial

WLPP in a nutshell for Java or C++ Programmers

A WLPP program is a C++ function named wain that has two parameters. The type of the first parameter is either int or int*. The type of the second parameter is int. The type of the result of the wain procedure is int.

Declarations, control structures and statements that may be used in WLPP are restricted to:

int or int*(declaration of a single int or int* variable with an unsigned integer constant or NULL initializer; all declarations in WLPP must precede all statements and control structures; every declaration must include an integer constant or NULL initializer)
if (must have an else clause)
while
return (must be the last statement in method)
println
= (i.e. assignment)

The clauses of if and while containing statements must be enclosed in braces (i.e. {}).

Expressions may contain only variable names, integers (written in decimal without a sign), unary & and *, and the binary (two operand) versions of the following operators:

    + - * / % == != <= >= < >

Arrays of consecutive integers may be dynamically allocated using new and delete [], but their elements can be accessed only using pointer dereferences, because WLPP does not include the C++ operator []. The // notation (and only the // notation) may be used for comments.

Example WLPP Program

//
// WLPP Program to compute:
//   a^b if 0 <= a,b < 10
//   -1 otherwise
//

int wain(int a, int b) {
   int counter = 0;
   int product = 0;
   product = 0-1;  // only binary minus
   if (a >= 0) {
      if (b >= 0) {
         if (a < 10) {
            if (b < 10) {
               product = 1;
               counter = 0;
               while (counter < b) {
                  product = product * a;
                  counter = counter + 1;
               }
            } else {} // must have else
         } else {} 
      } else {} 
   } else {}
   return product;
}