return-1;};Date.isLeapYear=function(year){return(((year%4===0)&&(year%100!==0))||(year%400===0));};Date.getDaysInMonth=function(year,month){return[31,(Date.isLeapYear(year)?29:28),31,30,31,30,31,31,30,31,30,31][month];};Date.getTimezoneOffset=function(s,dst){return(dst||false)?Date.CultureInfo.abbreviatedTimeZoneDST[s.toUpperCase()]:Date.CultureInfo.abbreviatedTimeZoneStandard[s.toUpperCase()];};Date.getTimezoneAbbreviation=function(offset,dst){var n=(dst||false)?Date.CultureInfo.abbreviatedTimeZoneDST:Date.CultureInfo.abbreviatedTimeZoneStandard,p;for(p in n){if(n[p]===offset){return p;}}
return null;};Date.prototype.clone=function(){return new Date(this.getTime());};Date.prototype.compareTo=function(date){if(isNaN(this)){throw new Error(this);}