simple get

get.js

/**
 * null-safe retrieval of objects and their property values from context
 * @function get
 * @param {String|String[]} path
 * @param {Object} [obj=this]
 * @return
 */
(function (HEAD) {
    var depthCache = {};
    var cache = {};
    function getDepth(depth) {
        if (!depthCache[depth]) {
            var params = "";
            var vars = "  var _0 = this";
            var body = false;
            var h, i;
            for (i = 0; i < depth; i += 1) {
                params += i ? (", $" + i) : "$" + i;
                vars += i ? (", _" + i) : "";
            }
            vars += ";\n";
            for (h = i - 1; i > 0; i -= 1, h -= 1) {
                if (!body) {
                    body = "_" + h + " === Object(_" + h + ") && ($" + h + " in _" + h + ") ? _" + h + "[$" + h + "]";
                } else {
                    body = "(_" + i + " = _" + h + "[$" + h + "], _" + i + ") && " + body;
                }
            }
            body = "  return " + (!body ? "_0;" : body + " : void(0);");
            depthCache[depth] = Function(params, vars + body);
        }
        return depthCache[depth];
    }
    function get(path, obj) {
        var params = path ? path.split ? cache[path] || (cache[path] = path.split("."), cache[path]) : path : [];
        return getDepth(params.length).apply(obj || this, params);
    }
    HEAD.get = get;
}(this));

getTests.js

//setup test objects
(function (HEAD) {
    var paths = {};
    HEAD.paths = paths;
    HEAD.obj = (function (start, end) {
        var i, next, obj, path, name;
        next = obj = {};
        path = "";
        for (i = 0; i < (end - start); i += 1) {
            name = String.fromCharCode(i + start);
            next = next[name] = (i%3 < 2 ? {} : i%2 === 0 ? [] : function () {});
            path += path.length ? "." + name : name;
            paths[i + 1] = path;
        }
        return obj;
    }(97, 123));
}(this));

//run tests
(function (tests, HEAD) {
    var i = tests.length;
    var test;
    while (i--) {
        test = tests[i];
        if (test !== "ignore") {
            switch (test[0]) {
                case "type":
                    console.assert(typeof get(test[2], test[3]) === test[4], test[1]);
                break;
                case "instance":
                    console.assert(get(test[2], test[3]) instanceof test[4], test[1]);
                break;
                default:
                    console.assert(get(test[2], test[3]) === test[4], test[1]);
            }
        }
    }
}([
    //type      message                                     param1                          param2      equals
    ["equals",  "should get global from global",            ,                               ,           this],
    ["equals",  "should get obj from global",               "obj",                          ,           obj],
    ["equals",  "should get obj from obj",                  null,                           obj,        obj],
    ["equals",  "should get obj from obj",                  ,                               obj,        obj],
    ["equals",  "should get obj from obj at depth 0",       paths[0],                       obj,        obj],
    ["equals",  "should get a from obj at depth 1",         paths[1],                       obj,        obj.a],
    ["equals",  "should get z from obj at depth 26",        paths[26],                      obj,        obj.a.b.c.d.e.f.g.h.i.j.k.l.m.n.o.p.q.r.s.t.u.v.w.x.y.z],
    ["equals",  "should not get x from a at depth 2",       paths[1] + ".x",                obj,        ],
    ["equals",  "should not get x from a at depth 3",       paths[1] + ".x.x",              obj,        ],
    ["instance","should return an array c from b",          paths[3],                       obj,        Array],
    ["equals",  "should return length 0 from array c",      paths[3] + ".length",           obj,        0],
    ["equals",  "should return length 0 from array c",      ["a", "b", "c", "length"],      obj,        0],
    ["type",    "should return a function f from e",        paths[6],                       obj,        "function"],
    ["type",    "should return a function apply from f",    paths[6] + ".apply",            obj,        "function"],
    ["equals",  "should return f.apply.length",             paths[6] + ".apply.length",     obj,        2],
    ["equals",  "should get d from obj at depth 4",         ["a", "b", "c", "d"],           obj,        obj.a.b.c.d],
    "ignore"
], this));

send.js

function send(fn, args, obj) {
    var f = fn;
        var o = this || obj;
        if (typeof fn === "string") {
            f = get(fn, o);
    }
    return f.apply(o, args);
}