code: function _getValidBezierParams(match) {
          var param,
              // take ease-in-out as default value in case there are no params yet (or they are invalid)
              def = [ ".42", "0", ".58", "1" ],
              oldIndex = match.index, // we need to store the old match.index to re-set the index afterwards
              originalString = match[0],
              i;
  
          if (match) {
              match = match[1].split(",");
          }
  
          if (match) {
              for (i = 0; i <= 3; i++) {
                  if (match[i]) {
                      match[i] = match[i].trim();
                      param = _convertToNumber(match[i]);
  
                      // Verify the param is a number
                      // If not, replace it with the default value
                      if (!param.isNumber) {
                          match[i] = undefined;
  
                      // Verify x coordinates are in 0-1 range
                      // If not, set them to the closest value in range
                      } else if (i === 0 || i === 2) {
                          if (param.value < 0) {
                              match[i] = "0";
                          } else if (param.value > 1) {
                              match[i] = "1";
                          }
                      }
                  }
  
                  if (!match[i]) {
                      match[i] = def[i];
                  }
              }
          } else {
              match = def;
          }
          match = match.splice(0, 4); // make sure there are only 4 params
          match = "cubic-bezier(" + match.join(", ") + ")";
          match = match.match(BEZIER_CURVE_VALID_REGEX);
  
          if (match) {
              match.index = oldIndex; // re-set the index here to get the right context
              match.originalString = originalString;
              return match;
          }
          return null;
      }
docs: Get valid params for an invalid cubic-bezier.
  
  @param {RegExp.match} match (Invalid) matches from cubicBezierMatch()
  @return {?RegExp.match} Valid match or null if the output is not valid