Map e Reduce em JavaScript - Post http://localhost8080.blogspot.com.br/2015/10/map-e-reduce-em-javascript.html

map-reduce.js

// map
var idList = list.map(function(entity) {
    return entity.id;
});

// reduce
var valueTotal = list.reduce(function(valueTotal, entity) {
    return valueTotal + entity.value;
}, 0);