A duplicate reference to a structure such as a variable, file or object. Contrast with "deep copy," which is an actual duplicate of the data. Shallow copy examples are shortcuts, symbolic references and programming pointers, all of which contain the address of and point to the data structure, but do not contain the data themselves.
(computing) A copy of a data structure which shares any linked structures with the original.
If you modify that, you'll modify all the shallow copies of the header that points to it.
To make a shallow copy of.
The bug came from trying to shallow-copy a mutable structure.