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Operators


Here are lists of the most commonly used operators and their meanings, with examples.

Table 1. Arithmetic operators

Operator Meaning Example
+ addition $a + $b
- subtraction $a - $b
* multiplication $a * $b
/ division $a / $b
% modulus $a % $b
++ increment $a++
-- decrement $a--

Table 2. Logical operators

Operator Meaning Example
&& and $a && $b
|| or $a || $b
! not !$a

Table 3. Assignment operators

Operator Meaning Example
= assign $a = $b
+= add to $a +=1
-= subtract from $a -=1
.= append $str.="foo"

Table 4. Relational operators used in string context

Operator Meaning Example
eq equivalent $str eq "foo"
ne not equivalent $str ne "foo"
gt greater than $str gt "123"
lt less than $str lt "123"
ge greater than or equal to $str ge "123"
le less than or equal to $str le "123"

Table 5. Relational operators used in numeric context

Operator Meaning Example
== equivalent $num == 100
!= not equivalent $num! = 100
> greater than $num>100
< less than $num<100
>= greater than or equal to $num>=100
<= less than or equal to $num<=100

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