1// before -- [_,_,NEW,REF,_,_]
2list.splice(list.indexOf(REF), 0, NEW))
3

1list.splice(2, 1, X)    // list == [a,b,X,d,e]
2

1list = [a,b,c,d,e]
2

1// after -- [_,_,REF,NEW,_,_]
2list.splice(list.indexOf(REF)+1, 0, NEW))
3

1.every(n => ...) => Boolean // ie9+
2.some(n => ..) => Boolean   // ie9+
3

1.filter(n => ...) => array
2

1re = list.splice(1)     // re = [b,c,d,e]  list == [a]
2re = list.splice(1,2)   // re = [b,c]      list == [a,d,e]
3

1.map(n => ...)   // ie9+
2.reduce((total, n) => total) // ie9+
3.reduceRight(...)
4

1list.push(X)            // list == [_,_,_,_,_,X]
2list.unshift(X)         // list == [X,_,_,_,_,_]
3list.splice(2, 0, X)    // list == [_,_,X,_,_,_]
4

1.find(n => ...)  // es6
2.findIndex(...)  // es6
3