B.2  Mathematical and Logical Operators

Sheerpower supports the following mathematical operators:

  +     addition
  -     subtraction
  *     multiplication
  /     division
  ^     exponentiation
  ++    increment a variable's value.. For example: counter++

Sheerpower supports the following logical operators:

  <     less than                  X is less than Y 
  <=    less than or equal to      X is less than or equal to Y
  =     equals                     X is equal to Y 
  >     greater than               X is greater than Y 
  >=    greater than or equal to   X is greater than or equal to Y
  <>    not equal to               X is not equal to Y 

  NOT   NOT X      TRUE  if X is false
  AND   X AND Y    TRUE  if X and Y are both true
  OR    X OR Y     TRUE  if either X or Y are true
  XOR   X XOR Y    TRUE  if X is true, or if Y is true, FALSE if X and Y are both true or both false
  IMP   X IMP Y    TRUE  if X is true and Y is false
  
  EQV   X EQV Y    TRUE  if X and Y are true, or 
                         TRUE  if X and Y are false, FALSE otherwise

In addition there are a lot of built-in mathematical functions. See common math functions and transcendental functions for details.

Order of Evaluation
Sheerpower always evaluates expressions in parentheses first. Parentheses, ( ), can be used to change the order of any of the following operations. If parentheses are nested, Sheerpower evaluates them from the inside out. For example:

                Z - (X / (Y+AMOUNT)) 

Sheerpower evaluates the expression Y + AMOUNT first. Next, it divides the X by that result. Finally, it subtracts the entire expression from Z.

• Sheerpower performs functions second.
• Sheerpower performs exponentiation.
• Sheerpower performs multiplication and division.
• Sheerpower performs addition and subtraction.
• Sheerpower performs relational operations from left to right. (The relational operators are: =, <, >, <=, >= and <>.) The only exception is the assignment of the result. The result is always assigned last.

Sheerpower performs logical operations in the following order:

NOT
AND
OR
XOR
IMP
EQV

For clarity, Parentheses can be used around every set of operations. This makes it easy to pick out the beginning and end of an operation, and will make absolutely clear what is intended without depending on the order of precedence of operators.