mutable.js

var Keys = require("object-keys")
var hasKeys = require("./has-keys")

module.exports = extend

function extend(target) {
    var sources = [].slice.call(arguments, 1)

    for (var i = 0; i < sources.length; i++) {
        var source = sources[i]

        if (!hasKeys(source)) {
            continue
        }

        var keys = Keys(source)

        for (var j = 0; j < keys.length; j++) {
            var name = keys[j]
            target[name] = source[name]
        }
    }

    return target
}