Operators in PERL - BunksAllowed

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Operators in PERL

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In this tutorial, various operators used in this language are discussed with examples. Let us have a look.

Arithmetic Operators

Usage of different arithmatic operators are shown in the following table.

Operator Usage
addition (+) $a + $b
subtraction (-) $a - $b
multiplication (*) $a * $b
division (/) $a / $b
modulus (%) $a % $b
exponent (**) $a ** $b

Equality Operators

These operators are also known as relational operator. If the operands are numeric, these operators can be used as shown in the following table.

Operator Usage for numeric data Usage for string data
eual to (==) ($a == $b) ($a eq $b)
not eual to (!=) ($a != $b) ($a ne $b)
comparison (<=>) ($a <=> $b) ($a cmp $b)
greater than (>) ($a > $b) ($a gt $b)
less than (<) ($a < $b) ($a lt $b)
greater than equals (>=) ($a >= $b) ($a ge $b)
less than equals (<=) ($a <= $b) ($a le $b)

Assignment Operator

Assignment operator is used to assign a value to a variable. The syntax of the operator usage is $c = $a + $b . The operator is also used with other arithmatic opeartos, like $c += $a .

Bitwise Operators

This operator works on bits and perform bit by bit operation. The operations are bitwise AND (&), OR (|), XOR (^), one's complement (~), left shift (<<), right shift (>>) .

Let us consider a = 60 and b = 13 . The binary representation of the variables are $a = 0011 1100 and $b = 0000 1101 . The bitwise operations can be performed on variables as shown below.

$a&$b = 00001100 $a|$b = 00111101 $a^$b = 00110001 ~$a = 11000011 $a << 2 $a >> 2

Logical Operators

There are following logical operators supported by Perl language. The operators are used as follow:

Operator style1 style2
Logical AND ($a and $b) ($a && $b)
Logical OR ($a or $b) ($a || $b)

Quote-like Operators

There are following Quote-like operators supported by Perl language. In the following table, a {} represents any pair of delimiters you choose.

Operator description
q{pqrs} a string within single quotes like 'pqrs'
qq{pqrs} a string within double quotes like "pqrs"
qx{pqrs} a string within inverted quotes like `pqrs`

Miscellaneous Operators

There are following miscellaneous operators supported by Perl language.

Operator description example
Binary operator dot (.) concatenates two strings. If $a = "abc", $b = "def" then $a.$b will give "abcdef"
Repetition (x) returns a string consisting of the left operand repeated the number of times specified by the right operand. ('-' x 3) will give ---
Range (..) returns a list of values counting from the left value to the right value (2..5) will give (2, 3, 4, 5)
Auto increment (++) increases integer value by one $a++ will give 11 if previous value is 10
Auto decrement (--) decreases integer value by one $a-- will give 9 if previous value is 10
Arrow (->) mostly used in dereferencing a method or variable from an object or a class name $obj->$a is used to access variable $a from object $obj.



Happy Exploring!

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