cmp | Returns -1 if less than, 0 if equal, and 1 if greater than |
=~ | Matched by regular expression |
!~ | Not matched by regular expression |
Compound Operators
Perl uses compound operators, similar to those used by C or awk, which can be used to combine other operations (such as comparisons or arithmetic) into more complex forms of logic. Table 25.3 shows the compound pattern operators and their behavior.
TABLE 25.3 Compound Pattern Operators in Perl
| Operator | Meaning |
|---|---|
&& | Logical AND |
|| | Logical OR |
! | Logical NOT |
() | Parentheses; used to group compound statements |
Arithmetic Operators
Perl supports a wide variety of math operations. Table 25.4 summarizes these operators.
TABLE 25.4 Perl Arithmetic Operators
| Operator | Purpose |
|---|---|
x**y | Raises x to the y power (same as x^y) |
x%y | Calculates the remainder of x/y |
x+y | Adds x to y |
x-y | Subtracts y from x |
x*y | Multiplies x times y |
x/y | Divides x by y |
-y | Negates y (switches the sign of y); also known as the unary minus |
++y | Increments y by 1 and uses value (prefix increment) |
y++ | Uses value of y and then increments by 1 (postfix increment) |
--y |
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