alt Hacker NewsI'm curious, for someone more familiar with Goose: how do you represent an arbitrary number of dynamically sized values? If you have a fixed number of stacks, it seems like only a fixed number of values can change size at any given time.
For instance, how would you represent a hash table where the values are strings and at random, the program inserts or deletes a random string?
This doesn't seem like something you could easily represent. The only way I can think of is to keep a stack that holds all of your strings, and you periodically compact it.
Edit: Maybe you could also have a separate stack for strings of various sizes. One each for strings less than 8, 16, ... bytes. But at that point you're basically implementing your own malloc by hand.
Edit: Fwiw I do think Goose is very cool! I've had to hand-roll a lot of similar stuff in Rust before to speed up memory management
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I'm not familiar with Goose, but I'm guessing you could define a single stack and put your dynamically sized values in it. Essentially rewriting a memory allocator on top of Goose's stacks. This is what they seem to be doing here: https://github.com/aardappel/goose/blob/master/samples/13_li...
> how would you represent a hash table where the values are strings and at random, the program inserts or deletes a random string?
Goose has a built-in generic hash table called dictionary<K, V>, provided by its standard library.
https://aardappel.github.io/goose/docs/stdlib.html#dictionar...
I think the limit of this would be creating your own allocator that works with the stacks, but you could probably stop short of that in most cases.
It's not entirely mad to do it this way, and I can see some benefits. For one, you might have multiple of these pools across the program for different data-types, which would make allocating to any one of them a cheaper operation. It is much more reference safe since you are only ever freeing stuff in a certain context and you can still never have dangling pointers. When you look at memory safe languages, they all default to this eventually. Like Rust in the advanced case will have you implementing your own allocator, lot's of games use this thing called ECS which is essentially a kind of allocator. Goose would just have it be more common.
Certainly, this is a language where you get the most benefits if you are able to structure your data usage such that things of similar lifetimes sit together in arrays.
For example, you can build up a tree of all variable sized nodes inside a single array.
Where it gets interesting is if you must arbitrarily delete tree nodes, and you can't structure it to do that in stack order. The language has various tools for this, like fixed arrays with capacity, or pools of either single elements or runs of elements.