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3. Expressions and Operators > Assignment Expressions

Assignment Expressions

JavaScript uses the = operator to assign a value to a variable, object property, or array element. For example:

i = 0    // Set the variable i to 0.
o.x = 1  // Set the property x of object o to 1.

The = operator expects its left-side operand to be an lvalue: a variable or object property or array element. It expects its right-side operand to be an arbitrary value of any type. The value of an assignment expression is the value of the right-side operand. As a side effect, the = operator assigns the value on the right to the variable or property on the left so that future references to the variable or property evaluate to the value.

The assignment operator has right-to-left associativity, which means that when multiple assignment operators appear in an expression, they are evaluated from right to left. Thus, you can write code like this to assign a single value to multiple variables:


  

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