Event Sourcing • Greg Young • GOTO 2014

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Recommends Leftium · 2023-02 · on “Ask HN: Just Finished Stroustrup's 'Practice and Principles'. What Next?”

It depends on what your goals are... I haven't read 'Practice and Principles', but I assume it focuses mostly on the OOP programming paradigm. I'd explore the functional programming paradigm. I say paradigm because it's possible to implement the functional paradigm in a traditionally imperative/OOP language like C++. (And it's possible to implement OOP/imperative paradigm in traditionally functional languages like Scheme/Lisp.) So learning functional concepts can improve your C++ programming, at both the "strategic" (program design) and "tactical" levels (implementation in code). Quick summary of the promises of functional programming: 1. Program design/code that is easier to reason about/de

Cites pvivera · 2015-04 · on “Open Source .NET libraries that make your life easier”

I started use Circus. New and in active development. Greg Young mentioned at GOTO talk last year ( [this video] ) [LINK]

Cites orksliver · 2017-03 · on “Solving State Explosion with Petri-Nets and Vector Clocks”

> But if someone can explain the problem better, I'm all ears. Assuming you mean it... Here's a youtube video about the benefits and attributes of event-sourcing. [this video] Though the demo project is presented in the browser, I'm trying to demonstrate that I can model the game of Tic-Tac-Toe using a much smaller and comprehensible (I hope) graph. Additionally - because these are mathematical graphs I'm speaking of - it means the 'program' that the graph represents - can be expressed as pure math ( which is nifty to say the least ) A classic DFA would have to represent all the permutations of the board like so: [LINK]

Cites Leftium · 2024-03 · on “Ask HN: Explain to me why functional programming is better like I'm stupid”

I think your specific question can be answered by this video. It explains how all branching was removed by refactoring an imperative-style function into functional-style. The original code is on the top, the refactored code is on the bottom: [LINK] Besides being shorter and easier to reason about, functional-style can be easier to test because there are fewer logical paths to test (statement/condition/branch/etc coverage). Of course, it's still totally possible to write bad code in a functional-style! Some little advantages of creating arrays in functional-style TS (vs declaring an empty array [] and filling it imperatively with `push()`): - TS can autumatically infer the type of the array;

Cites Leftium · 2024-03 · on “Ask HN: Functional Programming Hype”

Learning Functional Programming can provide immediate benefits. However, FP practitioners tend to be bad at teaching/explaining (to non-mathematicians) and even worse at marketing[0]. I've attached a list of good resources on FP at the end of this comment. I also wrote an article on the benefits of functional programming: [LINK] Functional programming is more of a spectrum; not an "all or nothing" concept. You can write FP-style programs in non-FP languages. (And you can use non-FP style in FP languages.) Understanding FP will help you write better non-FP code. Simple example: I have switched from declaring an empty array [], then filling it via a loop to declaring the same array with values

Cites Leftium · 2026-01 · on “Ask HN: Do you bother making state changes reversible?”

There are forms of state that are reversible: essentially, you store read-only events instead of writing to existing state. The main disadvantages are more complexity and performance issues. Examples: - Event sourcing: [this video] - CRDT - At the DB layer: [LINK] - You can also do it at the code level (but this is more like keeping copies of the old state): [LINK]