DataScript backwards relation

gistfile1.js

var d = require('datascript');

var db = d.db_with(
    d.empty_db({
        'chicken': { ':db/valueType': ':db.type/ref' }
    }),
    [
        { ':db/id': 1, 'name': 'Chicken' },
        { ':db/id': 2, 'name': 'Egg 1', 'chicken': 1 },
        { ':db/id': 3, 'name': 'Egg 2', 'chicken': 1 }
    ]
);

// When using `entity`, `_chicken` will get both eggs:
var chicken = d.entity( db, 1 );
var eggsViaEntity = chicken.get('_chicken').map( function( egg ) {
    return egg.get('name');
} );
console.log( eggsViaEntity );
// => [ 'Egg 1', 'Egg 2' ]

// When using `pull` only a single egg is returned:
var eggsViaPull = d.pull( db, '["name" {"_chicken" ["name"]}]', 1 );
console.log( eggsViaPull );
// => { 'name': 'Chicken', '_chicken': { 'name': 'Egg 1' } }