Method chain
function reduceComponents (components) {
return components
.map((c) => c.props.children)
.map((children) => React.Children.toArray(children))
.reduce((a, b) => a.concat(b), [])
https://github.com/zeit/next.js/blob/canary/lib/head.js\#L19
variable declaration
var m = (i1 == null ? array.length : i1) - (i0 = i0 == null ? 0 : +i0),
t,
i;