For more research, the term you want to look for is "Persistent data structures": https://en.wikipedia.org/wiki/Persistent_data_structure
There are also good talks on the topic, here is one from Rich Hickey: https://www.youtube.com/watch?v=toD45DtVCFM On Mon, Aug 24, 2020 at 3:08 PM Bulent Erdemir <[email protected]> wrote: > Oh, that's it, then. :) > > Thank you for your quick reply. I'll follow up with the book and more > research. > > On Mon, Aug 24, 2020 at 3:32 PM Derek Kraan <[email protected]> wrote: > >> The short answer is that the BEAM does not do a full copy of a map for >> every update. >> >> For the long answer you could refer to this book: >> https://www.amazon.com/Purely-Functional-Data-Structures-Okasaki/dp/0521663504 >> >> On Mon, Aug 24, 2020, at 14:28, Bulent Erdemir wrote: >> >> Hi, >> >> Elixir applications, due to immutability principle, create a copy of a >> data structure once that structure is modified (transformed) and if the >> structure's new value is to be kept via assignment to a variable. Hence, >> for example, when a Map is visited and some its members are modified , for >> each modification a copy of the whole Map is created. I understand that >> creating a new variable is as simple as bumping up a pointer in memory, >> however, the whole Map is copied over and over again while it's being >> modified in the application. In other languages without the immutability >> principle, only the changed portion of the Map would be allocated in memory >> during a similar operation. >> >> In such a situation where there's this copying overhead in almost all >> data operations in an Elixir program, I would expect the system would run >> much slower compared to other languages. Yet, I've not seen mention of this >> problem anywhere on the web. So, probably, I'm missing something. Anyone >> please would care to comment on this ? >> >> Regards, >> Bülent Erdemir >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "elixir-lang-core" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/elixir-lang-core/CABgUW%2BQiD_Q8bKbe8hV5Q6Lh3PbgVxthOf7zRMASA4qiwqmbrA%40mail.gmail.com >> <https://groups.google.com/d/msgid/elixir-lang-core/CABgUW%2BQiD_Q8bKbe8hV5Q6Lh3PbgVxthOf7zRMASA4qiwqmbrA%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "elixir-lang-core" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/elixir-lang-core/03738aa6-3665-4a4d-a6de-4475d0a0a228%40www.fastmail.com >> <https://groups.google.com/d/msgid/elixir-lang-core/03738aa6-3665-4a4d-a6de-4475d0a0a228%40www.fastmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to the Google Groups > "elixir-lang-core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elixir-lang-core/CABgUW%2BRz7-yWu%2Bf3ZW%2BNjT7C%2BxHCnoAEA5eCFCnXPMfZpZ38kg%40mail.gmail.com > <https://groups.google.com/d/msgid/elixir-lang-core/CABgUW%2BRz7-yWu%2Bf3ZW%2BNjT7C%2BxHCnoAEA5eCFCnXPMfZpZ38kg%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "elixir-lang-core" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/elixir-lang-core/CAGnRm4KytOYyJ2qZKzZLhJ%2BA82hH%2BL8yOPCa%2B4OcEVRcV9k37Q%40mail.gmail.com.
