If you are a C, C++, or Java programmer, most of the
JavaScript operators should already be familiar to you. Table 5-1 summarizes the operators; you can
use this table as a reference. Note that most operators are
represented by punctuation characters such as + and =.
Some, however, are represented by keywords such as delete and instanceof. Keyword operators are regular
operators, just like those expressed with punctuation; they are simply
expressed using a more readable and less succinct syntax.
Table 5-1. JavaScript operators
P
A
Operator
Operand type(s)
Operation performed
15
L
.
object, identifier
Property access
L
[]
array, integer
Array index
L
(
)
function, arguments
Function call
R
new
constructor call
Create new object
14
R
++
lvalue
Pre- or post-increment
(unary)
R
--
lvalue
Pre- or post-decrement
(unary)
R
-
number
Unary minus
(negation)
R
+
number
Unary plus (no-op)
R
~
integer
Bitwise complement
(unary)
R
!
boolean
Logical complement
(unary)
R
delete
lvalue
Undefine a property
(unary)
R
typeof
any
Return datatype
(unary)
R
void
any
Return undefined value
(unary)
13
L
*, /, %
numbers
Multiplication, division,
remainder
12
L
+, -
numbers
Addition, subtraction
L
+
strings
String concatenation
11
L
<<
integers
Left shift
L
>>
integers
Right shift with sign
extension
L
>>>
integers
Right shift with zero
extension
10
L
<, <=
numbers or strings
Less than, less than or
equal
L
>, >=
numbers or strings
Greater than, greater than or
equal
L
instanceof
object, constructor
Check object type
L
in
string, object
Check whether property
exists
9
L
==
any
Test for equality
L
!=
any
Test for inequality
L
===
any
Test for identity
L
!==
any
Test for nonidentity
8
L
&
integers
Bitwise AND
7
L
^
integers
Bitwise XOR
6
L
|
integers
Bitwise OR
5
L
&&
booleans
Logical AND
4
L
||
booleans
Logical OR
3
R
?:
boolean, any, any
Conditional operator (three
operands)
2
R
=
lvalue, any
Assignment
R
*=, /=, %=, +=, -=, <<=, >>=, >>>=, &=, ^=, |=
lvalue, any
Assignment with
operation
1
L
,
any
Multiple evaluation
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