B.9 Operator Precedence

Operator precedence determines the order in which the operations are applied. For instance, in Perl, the expression:

3 + 3 * 4

isn't evaluated left to right, which calculates 3 + 3 equals 6, and 6 times 4 results in a value of 24; the precedence rules cause the multiplication to be applied first, for a final result of 15. The precedence rules are available in the perlop manual page and in most Perl books. However, I recommend you use parentheses to make your code more readable and to avoid bugs. They make these expressions unambiguous; the first:

(3 + 3) * 4

evaluates to 24, and the second:

3 + (3 * 4)

evaluates to 15.