// 93 byte length
function(a){a={}.toString.call()[8];return{f:a=='U',o:a=='W',s:a=='D',c:a=='g',i:!a||a=='O'}}
/* alternative 77 byte length
function(){return{U:'f',W:'o',D:'s',g:'c',O:'i'}[{}.toString.call()[8]]||'i'}
*/