Function toValue

app/src/static/js/react-bootstrap.js:4650–4692

* Converts a string containing value + unit into a px value number * @function * @memberof {modifiers~offset} * @private * @argument {String} str - Value + unit string * @argument {String} measurement - `height` or `width` * @argument {Object} popperOffsets * @argument {Object} referenceOffse

(str, measurement, popperOffsets, referenceOffsets)

function toValue(str, measurement, popperOffsets, referenceOffsets) {
  // separate value from unit
  var split = str.match(/((?:\-|\+)?\d*\.?\d*)(.*)/);
  var value = +split[1];
  var unit = split[2]; // If it's not a number it's an operator, I guess

  if (!value) {
    return str;
  }

  if (unit.indexOf('%') === 0) {
    var element = void 0;

    switch (unit) {
      case '%p':
        element = popperOffsets;
        break;

      case '%':
      case '%r':
      default:
        element = referenceOffsets;
    }

    var rect = getClientRect(element);
    return rect[measurement] / 100 * value;
  } else if (unit === 'vh' || unit === 'vw') {
    // if is a vh or vw, we calculate the size based on the viewport
    var size = void 0;

    if (unit === 'vh') {
      size = Math.max(document.documentElement.clientHeight, window.innerHeight || 0);
    } else {
      size = Math.max(document.documentElement.clientWidth, window.innerWidth || 0);
    }

    return size / 100 * value;
  } else {
    // if is an explicit pixel unit, we get rid of the unit and keep the value
    // if is an implicit unit, it's px, and we return just the value
    return value;
  }
}
/**
 * Parse an `offset` string to extrapolate `x` and `y` numeric offsets.
 * @function