copy smart object, paste in new doc, no longer smart

[squirpy]

Here is the relevant part:

app.activeDocument = backArt;
var backDesign = backArt.activeLayer;
backDesign.copy();
app.activeDocument = backTemp;
app.activeDocument.paste();

If the layer I copy is a smart object, it no longer is when pasted.  Is there some way to modify this or otherwise effectively copy and paste a layer that is a smart object?

[squirpy · Accepted solution]

Never-mind.  I was able to solve the problem by using duplicate instead of copy.

[Kukurykus]

Just in case you'd like to duplicate it to other document and you wouldn't know how:

activeDocument.activeLayer.duplicate(documents[1].activeLayer, ElementPlacement.PLACEBEFORE)