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web api instance property

CSSMathValue: operator property

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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.

InterfaceValue
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'
Interactive exampleOpen the canonical MDN source to run this embedded demo.

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

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.