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Python

Posted by Timothy Tseng
Timothy Tseng
3,292 Points

Can someone explain further why copy.copy is used

So from my understanding Python automatically passes all parameters by reference and variables in Python are actually pointers themselves.

So basically, if we were NOT to use copy.copy in Kennith's example where he calls javascriptobject.JavaScriptObject(2, [1,2,3]) what's happening is that all the lists created are all "pointing" to the same place in memory where [1,2,3] is stored, thus if there was ever a change to the list passed, then all the lists created by javascriptobject.JavasScriptObject would be changed as well.

BUT, by using copy.copy we are making the same list, but storing them in different memory address

Is my understanding correct?

1 Answer

Steven Parker
Steven Parker
229,644 Points
Steven Parker
Steven Parker
229,644 Points

You're quite right. A ".copy()" of a list is an entirely new duplicate list and not a reference to the original.