The subtraction assignment operator (-=) subtracts the value of the right operand from a variable and assigns the result to the variable.
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Syntax
Operator: x -= y Meaning: x = x - y
Examples
Using subtraction assignment
// Assuming the following variable // bar = 5 bar -= 2 // 3 bar -= 'foo' // NaN
Specifications
| Specification |
|---|
| ECMAScript (ECMA-262) The definition of 'Assignment operators' in that specification. |
Browser compatibility
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