qck.hlp (Table of Contents; Topic list)
Hierarchy of Operations
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 Hierarchy of Operations
 
 ■ When several Visual Basic operators occur in the same statement, they are
   executed in the following order:
 
         1. Arithmetic Operations
              a. Exponentiation (^)
              b. Negation (-)
              c. Multiplication and division (*, /)
              d. Integer division (\)
              e. Modulo arithmetic (MOD)
              f. Addition and subtraction (+, -)
 
         2. Relational Operations (=, >, <, <>, <=, >=)
 
         3. Logical Operations
              a. NOT
              b. AND
              c. OR
              d. XOR
              e. EQV
              f. IMP
 
 ■ An exception to the order of operations listed above occurs when an
   expression has adjacent exponentiation and negation operators. In this
   case, the negation is done first. For example:
 
         PRINT 4 ^ - 2
 
   prints the value .0625, not -16.
 
 ■ If the operations are different and are of the same level, the leftmost
   one is executed first and the rightmost last:
 
         A = 3 + 6 / 12 * 3 - 2        'A = 2.5
 
   In this case, the order of operations is:
 
         1. 6 / 12   (= 0.5)
         2. 0.5 * 3  (= 1.5)
         3. 3 + 1.5  (= 4.5)
         4. 4.5 - 2  (= 2.5)
 
 ■ In a series of additions or a series of multiplications, there is no fixed
   evaluation order. Either 3 + 5 or 5 + 6 may be calculated first in the
   following statement:
 
         C = 3 + 5 + 6
 
 ■ To control the order in which Visual Basic performs operations, you can
   use parentheses:
 
         B = (5 * 3) / (2 + 1)
 
   In this case, the order of operations is:
 
        1. 5 * 3 (= 15)
        2. 2 + 1 (= 3)
        3. 15 /3 (= 5)
 
 ■ Usually this does not cause problems. However, it may cause a problem if
   you have a series of FUNCTION procedure calls in your program:
 
         C = Incr(X) + Decr(X) + F(X)
 
 ■ If any of the three FUNCTION procedures given above modifies X or changes
   shared variables, the result depends on the order in which Visual Basic
   does the additions. You can avoid this situation by assigning the results
   of FUNCTION calls to temporary variables and then performing the addition:
 
         T1 = Incr(X) : T2 = Decr(X) : T3 = F(X)
         C = T1 + T2 + T3
 
 See: Expressions and Operators Summary  See: Arithmetic Operators