I think "isomorphic" in this context means that the two datums are interchangeable. Not necessarily residing in the same memory location, though. eq is used to find out if it's actually the same reference.

Besides, some languages/libraries can imlement a copy-on-write strategy (for example, QString in the Qt C++ library) that defy simple definitions.

In reply to Re^3: Do you consider these different or the same? by spurperl
in thread Do you consider these different or the same? by demerphq

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