I'm not sure singleton is really useful for modern JS/TS. I tend to just have a module with a declared export or set of exports for this use case.
An example is normalizing values either injected by the server or set via a request from the api or config server. As the first script.
ex: <script src="https://config-server/base.js"></script>
Then in-code, I use a module that normalizes the global variables the base.js sets. `global.__BASE__` which will include language strings, feature flags/toggles and any service urls. I use feature/base.js from my code, that exposes the globals in a normalized patter... such as the current language and extra interfaces.
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On observers, I tend to favor the simpler model that a node-style event emitter has. For the DOM, you can subscribe and trigger non-standard events, though TS makes this difficult.
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Factories are rarely needed in JS/TS, I tend to bucket them in with IoC and DI,
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It's good to know the pattern, but the JS/TS platforms, language and tooling allows for simpler solutions in JS. This is just my own opinion.
tracker1 1282 days ago. link 2 points ▲ ▼