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This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The CSSMathValue.operator read-only property of the CSSMathValue interface indicates the operator that the current subtype represents. For example, if the current CSSMathValue subtype is CSSMathSum, this property will return the string "sum".


var aString = CSSMathValue.operator;


A String.

Interface Value
CSSMathSum "sum"
CSSMathProduct "product"
CSSMathMin "min"
CSSMathMax "max"
CSSMathClamp "clamp"
CSSMathNegate "negate"
CSSMathInvert "invert"


We create an element with a width determined using a calc() function, then console.log() the operator.

<div>My width has a <code>calc()</code> function</div>

We assign a width with a calculation

div {
  width: calc(50% - 0.5vw);

We add the JavaScript

const styleMap = document.querySelector('div').computedStyleMap();

console.log( styleMap.get('width') );                   // CSSMathSum {values: CSSNumericArray, operator: "sum"}
console.log( styleMap.get('width').values );            // CSSNumericArray {0: CSSUnitValue, 1: CSSMathNegate, length: 2}
console.log( styleMap.get('width').operator );          // 'sum'
console.log( styleMap.get('width').values[1].operator ) // 'negate'

The CSSMathValue.operator returns sum for the equation and negate for the operator on the second value.


Specification Status Comment
The definition of 'CSSMathValue.operator' in that specification.
Working Draft Initial definition.

Browser compatibility

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