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CSSMathValue: operator property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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".

Value

A String.

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

Examples

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.

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
operator 66 79 No 53 16.4 66 No 47 16.4 9.0 66 16.4

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https://developer.mozilla.org/en-US/docs/Web/API/CSSMathValue/operator