copy performs a deep clone on the supplied value. It currently supports circular (and non-circular) references, dates, regular expressions, functions, buffers and typed arrays. Note that copied buffers and typed arrays will still be views to the same underlying source.

require('copy')([ 1, 2, 3, { a: 'b' } ]) // -> [ 1, 2, 3, { a: 'b' } ]

npm install copy

Public domain.