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Comment by bradleybuda | Hacker News Reader

I use this pattern a lot (and I often find myself wishing I used it more). Another way to think about this is "noun-ification" (aka the Command pattern) - instead of invoking a function directly, capture all of its arguments, serialize them to some "store", then provide the ability to rehydrate them and actually run it.

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Interesting you used the term hydrate because I only hear that used when talking about front-end web development (specifically Next and React) and it's a relatively new term. The "Hydration (web development)" Wikipedia article was only created in December 2020. https://en.wikipedia.org/wiki/Hydration_(web_development)

I feel like serialize/deserialize or marshal/demarshal are more common in broader computer science contexts.

"Hydrate" is much older than 2020. Here's a StackOverflow reference from 2011 [1], for instance. I first heard it used around that time, for loading objects from databases (in a banking context).

[1] https://stackoverflow.com/a/4929478

I came here to say basically the same thing. To me, this reads like an example of the Command pattern, which is one of my favorite, most-used patterns.

The idea of taking some chunk of imperative behavior and reifying it into an object that can perform that behavior is very powerful:

* It allows you to attach other metadata to the object so that code can ask questions about it: "Do you perform IO?" "Can you be reverted?" It lets surrounding code introspect over operations in useful ways.

* It allows you to separate the code that creates the command from the code that performs it (what this blog post is about). This can nicely decouple "strategy"-type code from "execution harness" type code. Both of those are often fairly complex in their own right, so a pattern that lets you build a nice abstraction layer between them can be very helpful.

* It allows the command object to support multiple related operations. The most common example, which I deeply love, is implementing undo. A Command object for some UI operation can also support a separate method to undo the same operation. Your undo stack is then just a list of these Command objects.

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