What is the ^= operator?

Question

I just came across an answer here on SO where a code example (in what I thought was java) used an operator I have never seen before: ^=. I searched google and SO and haven't been able to find it anywhere else and when I tried to test it out using java, eclipse went crazy. Maybe it was just a typo in the answer, I'm not sure. What is this operator? Does it have a name? What language is it from or used in?

score 9 · Answer 1 · answered Dec 27 '13 at 01:23

9

It is the C/C++/C#/Java/Javascript/Perl bitwise xor assignment operator.

answered Dec 27 '13 at 01:23

ldav1s

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score 5 · Accepted Answer · answered Dec 28 '13 at 05:05

This is the C/C++/C#/Java/Javascript/Perl/PHP/Pike bitwise XOR assignment operator.

An XOR (exclusive or) conditional statement evaluates to true if and only if one of the two operands involved is true.

Example:

0 ^ 0 = false
1 ^ 0 = true
0 ^ 1 = true
1 ^ 1 = false //Regular OR would evaluate this as true

In the same way that you can use += -= *= /= etc... this operator can be combined with an equals sign to perform assignment upon completion.

x += 1; //Same as x = x + 1;
t ^= f; //Same as t = t ^ f;

boolean a = false;
boolean b = true;
a ^= b; //a now evaluates to true;

See Java Operators.

score 2 · Answer 3 · answered Dec 27 '13 at 01:22

2

It would depend on the language, but ^ is typically an exclusive-or (example languages: java, c-family); a ^= b is shorthand for a = a^b.

answered Dec 27 '13 at 01:22

Scott Hunter

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@csmckelvey Look att http://en.wikipedia.org/wiki/Xor The truth-table: 0 ^ 0 = 0, 0 ^ 1 = 1, 1 ^ 0 = 1, 1 ^ 1 = 0 – some Dec 27 '13 at 01:28

score 2 · Answer 4 · answered Dec 27 '13 at 01:24

2

take a look here

http://docs.oracle.com/javase/tutorial/java/nutsandbolts/operators.html and http://docs.oracle.com/javase/tutorial/java/nutsandbolts/op3.html

but it is a Bitwise Exclusive or with assignment

answered Dec 27 '13 at 01:24

Doon

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score 0 · Answer 5 · answered Dec 27 '13 at 01:23

0

In jQuery it means "starting with this"

For example id^='my_'

means "id starts with 'my_'"

answered Dec 27 '13 at 01:23

dkellner

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Why write an answer about jQuery if the question is about Java? (see tags) – Aurelio De Rosa Dec 27 '13 at 01:43
@AurelioDeRosa At the time when this answer was written, there where no tag about java, only `operators`. – some Dec 27 '13 at 02:44
1

Yep, the text still ends like "What language is it from or used in?" – dkellner Dec 27 '13 at 08:05

score 0 · Answer 6 · answered Dec 27 '13 at 01:25

0

In the php manual it says that ^ is the bitwise XOR operator. Here's the link

answered Dec 27 '13 at 01:25

Dries

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What is the ^= operator?

6 Answers6

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