white kid gloves while she was talking.  `How CAN I have done
that?' she thought.  `I must be growing small again.'  She got up
and went to the table to measure herself by it, and found that,
as nearly as she could guess, she was now about two feet high,
and was going on shrinking rapidly:  she soon found out that the
cause of this was the fan she was holding, and she dropped it
hastily, just in time to avoid shrinking away altogether.

toValue(str, measurement, popperOffsets, referenceOffsets) {\n  // separate value from unit\n  const split = str.match(/((?:\\-|\\+)?\\d*\\.?\\d*)(.*)/);\n  const value = +split[1];\n  const unit = split[2];\n\n  // If it's not a number it's an operator, I guess\n  if (!value) {\n    return str;\n  }\n\n  if (unit.indexOf('%') === 0) {\n    let element;\n    switch (unit) {\n      case '%p':\n        element = popperOffsets;\n        break;\n      case '%':\n      case '%r':\n      default:\n        element...