I'm trying to concat two arrays of objects with lodash. I have these two array and I use concat operator in this way:

 var array1 = [{ id: 1, name: 'doc1' }, { id: 2, name: 'doc2' }];

 var array2 = [{id:1, name:'doc1'}, {id:3, name:'doc3'}, {id:4, name:'doc4'}];



 var array3 = _.concat(array1, array2);

I would like an array like this

 [{id:1, name:'doc1'}, {id:2, name:'doc2'}, {id:3, name:'doc3'}, {id:4, name:'doc4'}]]

But with concat function I obtain an array like this:

  [{ id: 1, name: 'doc1' }, { id: 1, name: 'doc1' }, { id: 2, name: 'doc2' }, { id: 3, name: 'doc3' }, { id: 4, name: 'doc4' }]]

I want to avoid the repetition of an object with the same id...Which kind of operator can I use?