Cycymomo
8/23/2013 - 4:11 PM

140bytes - getDay (based on french perpetual calendar algo : https://fr.wikipedia.org/wiki/Calendrier_perp%C3%A9tuel#Version_variante_m.C3.A

// 140bytes - http://www.developpez.net/forums/d1362763/webmasters-developpement-web/javascript/ludique-defis-code-en-tweet/
(function(d,t,y){
y=d.getFullYear();return t[(y%100*1.25+'0642'[(y/100-15)%4^0]*1+'033614625035'[d.getMonth()]*1+d.getDate()-!!((!(y%4)&&y%100)||!(y%400)))%7^0]
})(new Date(1789,6,14),['dimanche', 'lundi', 'mardi', 'mercredi', 'jeudi', 'vendredi', 'samedi']);