src/constraint/weekofmonth.js
function(d) {
    return d.wm || (d.wm =
      (later.D.val(d) +
      (later.dw.val(later.M.start(d)) - 1) + (7 - later.dw.val(d))) / 7);
  }
function(d) {
    return d.wm || (d.wm =
      (later.D.val(d) +
      (later.dw.val(later.M.start(d)) - 1) + (7 - later.dw.val(d))) / 7);
  }
function ( d ) { return d . wm || ( d . wm = ( later . D . val ( d ) + ( later . dw . val ( later . M . start ( d ) ) - 1 ) + ( 7 - later . dw . val ( d ) ) ) / 7 ) ; }
The week of month value of the specified date.

@param {Date} d: The date to calculate the value of
The week of month value of the specified date .