var meta = {

    name: "person_list",

    type: [],

    component: [{

        name: 'black_hair',

        type: {},

        component: {

            name: 'list',

            type: []

        }

    }]

};

​

var myObject = {

    person_list: [{

        asdfa: {

            list: [

                'bob',

                'john',

                'allen']

        }

    }]

};

​

function defined(meta, obj) {

    if (meta.name == 'list' && obj[meta.name] && obj[meta.name].length) {

        return true;

    }

    if (!obj[meta.name]) {

        return false;

    };

    if (Object.prototype.toString.call(meta.type) === '[object Array]' && !obj[meta.name].length) {

        return false;

    } else if (Object.prototype.toString.call(meta.type) === '[object Array]' && obj[meta.name].length) {

        for (index in obj[meta.name]) {

            return defined(meta.component[index], obj[meta.name][index]);

        }

    } else if (Object.prototype.toString.call(meta.type) === '[object Object]') {

        return defined(meta.component, obj[meta.name]);

    }

}

​

console.log(defined(meta, myObject));