Purely functional data structures

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1. wanderer2323Jul 2026
   A good place to plug my favorite thesis to read: Okasaki’s “purely functional data structures” https://www.cs.cmu.edu/~rwh/students/okasaki.pdf .

   Very soothing and moves fast.

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2. quotemstrMay 2026
   There are books about languages, and then there are books about timeless truths. The former? Toilet paper. The latter? Treasures. Worth reading:

   - Okasaki, Purely Functional Data Structures https://www.cs.cmu.edu/~rwh/students/okasaki.pdf

   - The Garbage Collection Handbook https://gchandbook.org/

   - The Dragon Book - https://faculty.sist.shanghaitech.edu.cn/faculty/songfu/cav/... (yes, it's old, but I still like the end-to-end, all-in-one intro)

   - Windows Internals - https://learn.microsoft.com/en-us/sysinternals/resources/win...

   - Structure and Interpretation of Computer Programs - https://web.mit.edu/6.001/6.037/sicp.pdf

   - Concurrency Control and Recovery in Database Systems - https://www.microsoft.com/en-us/research/people/philbe/book/

   - Crafting Interpreters - https://craftinginterpreters.com/

   - What Every Programmer Needs to Know About Memory - https://people.freebsd.org/~lstewart/articles/cpumemory.pdf (the best thing Ulrich Drepper ever did)

   - An Introduction to Modern Cryptography - https://eclass.uniwa.gr/modules/document/file.php/CSCYB105/R...

   A good programming book gets better with age. If it's really about ideas and uses this or that technology for exposition, so much the better: the more remote in time the grammar of the examples, the more you can focus on the ideas. SICP being in Scheme is an advantage because you don't know Scheme yet; Windows Internals being about Windows teaches you generally good lessons in OS design by forcing you to contemplate a system alien to the Unix you probably know better.

   It's shocking how many of these seminal books are available for free and how few people read them. Yes, yes, you can get the same information from an LLM, but an LLM won't give you the guided tour through the whole rugged ideas-space and show you a reasonable peak. Order, emphasis, and expository style build intuition, so books (especially old ones) are worth reading.

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3. boisterousnessMay 2026
   These are good ...

   "Python for Data Analysis" by McKinney (2018)

   "The Go Programming Language" by Donovan and Kernighan (2016)

   "Hacker's Delight" by Warren (2013)

   "Algorithm Design Manual" by Skiena (2008)

   "Purely Functional Data Structures" by Okasaki (1998)

   "Structure and Interpretation of Computer Programs" by Abelson and Sussman (1985)

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4. throwaway81523Apr 2026
   I mean there's a whole book about this, "Purely Functional Data Structures" (2009) by Chris Okasaki.
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5. eruMay 2025
   The 'radix trick' also works for data structures.

   Okasaki's book 'Purely Functional Data Structures' has some nice examples.

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6. KingMobJan 2025
   > My main gripe with immutability is that making updated data requires building a full copy of the data again with the changes.

   That's not generally true. Many immutable languages are using "persistent" data structures, where "persist" here means that much of the original structure persists in the new one.

   For more, see:

   - Purely Functional Data Structures by Okasaki: https://www.cs.cmu.edu/~rwh/students/okasaki.pdf - Phil Bagwell's research - e.g., https://infoscience.epfl.ch/record/64398/files/idealhashtree...

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