The SVGAnimatedEnumeration interface describes attribute values which are constants from a particular enumeration and which can be animated.

baseVal

An integer that is the base value of the given attribute before applying any animations.

animVal

If the given attribute or property is being animated, it contains the current animated value of the attribute or property. If the given attribute or property is not currently being animated, it contains the same value as baseVal.

The SVGAnimatedEnumeration interface do not provide any specific methods.

Considering this snippet with a <clipPath> element: Its clipPathUnits is associated with a SVGAnimatedEnumeration object.

<svg viewBox="0 0 100 100" width="200" height="200">
  <clipPath id="clip1" clipPathUnits="userSpaceOnUse">
    <circle cx="50" cy="50" r="35" />
  </clipPath>

  <!-- Some reference rect to materialized to clip path -->
  <rect id="r1" x="0" y="0" width="45" height="45" />
</svg>

This snippet gets the element, and logs the baseVal and animValof the SVGClipPathElement.clipPathUnits property. As no animation is happening, they have the same value.

const clipPathElt = document.getElementById("clip1");
console.log(clipPathElt.clipPathUnits.baseVal); // Logs 1 that correspond to userSpaceOnUse
console.log(clipPathElt.clipPathUnits.animVal); // Logs 1 that correspond to userSpaceOnUse