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Comment by hakfoo | Hacker News Reader

That's always something I've found weird.

There are things that are "global state", at least in the sense that you're likely to care about them in a hundred disparate places. If you're writing a UI, odds are at some point you're going to want to see "current user ID", "language selection", etc.

Why can't we just say "it's global" rather than doing all sorts of plumbing to pipe these details around the code base? I know we have stuff like contexts, but it feels a strange workaround, like someone saying "I'm on a diet, no sugar... but put 12 teaspoons of honey in my tea."

I know that the standard line is that it's difficult to test globals, but maybe developing a better test mechanism is a more tractable problem than having to add extra infrastructure to reinvent globals.

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I think this is a bad take on an old premise. It's not that "global state is bad", rather, "global MUTABLE state is bad". Which is kind of right but for the wrong reasons. Truth is, "mutable state" is bad and "mutable global state" is even worse. That comes from the old times of OOP when people insisted in "encapsulating" state and relied on mutation.

It's sort of a logical fallacy. How could global state be bad if reading from a database o an API is essentially that? The problem is mutation, that if global state is mutated somewhere, other places that read the same state don't know about it.

Modern state managment instead is immutable and is not even an original idea of React. Redux was basically copied from Elm's state management.

It really should be global, if it's global state. Maybe not directly in the javascript global (window) context, but part of a shared singleton, in an obvious (or at least consistent) way, or similar.

The simplest and most obvious pattern I've ever used was essentially an angularjs (1.x) directive that allowed templates to grab named references to services and directly reference that state. Mutations were also exposed on the services as plain old functions, and it all just kind of worked. Looking at a template, it was blatantly obvious where the data and methods came from. The two way binding just made it dead simple to grok what was going on once all the layers of abstraction (controllers in the AngularJS world) that might rename things or make up new clever abstractions were gone.

I've built with React a half dozen times now, and I still haven't found anything that got me close to that level of simplicity. I'd say most of my experience has been that it's at least 10x more complex with all the gymnastics you have to do to keep the data flow unidirectional.

This reminds me of a mithril project where my state management library was just a global variable. It was a breath of fresh air: simple code, snappy UI, no convoluted debugging.

Yep, Mithril's redraw system is definitely one of its strengths since there is no plumbing necessary. You're free to do whatever you want without any weird adapter libraries. You can build some decently robust state containers without dependencies or Mithril-specific code[1].

[1] https://mithril-by-examples.js.org/examples/tweeter-box/

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