Happy new year, Guys. I ‘d like to discuss about StableHashMap that simplify upgrade steps. When we use HashMap lib in Motoko, we have to implement these code. Because class variables can not be stable. var hp = HashMap.HashMap<Text, Nat>(1, Text.equal, Text.hash); stable var entries : [(…

I’m using this in my repo. Thank you. Do you still see this as a good approach?

Just use GitHub - ZhenyaUsenko/motoko-hash-map: Stable hash maps for Motoko and you’ll get 4-11x performance and a stable structure with no need to upgrade. We’ve been using GitHub - ZhenyaUsenko/motoko-migrations: Sample project structure to implement migrations in motoko as an upgrade pattern and…

[image] skilesare: Just use GitHub - ZhenyaUsenko/motoko-hash-map: Stable hash maps for Motoko and you’ll get 4-11x performance and a stable structure with no need to upgrade. We’ve been using GitHub - ZhenyaUsenko/motoko-migrations: Sample project structure to implement migrations in motoko as…

No. You would use them in conjunction. You don’t need migrations, but if you ever change something in your hashmap, you need to upgrade all your objects to the new types, and migrations gives you a pattern to do that with.

Perfect. So, as long as the types the hashmap stores don’t change, I don’t need to worry about migrations, not even through updates. Correct? Actually I’m getting errors trying to use that repo: [image] Not sure if it’s due to the way I imported it: // From https://github.com/ZhenyaUsenko/motok…

Did you able to make it work the import Map “mo:hashmap/Map”;? if yes, how did you do it?

Yes, I did import Map "motoko-hash-map/src/Map/Map"; // From https://github.com/ZhenyaUsenko/motoko-hash-map and just placed the complete directory there. There’s probably a better way though, using vessel I think, but I’m using mops and they’re mutually incompatible.

Stable HashMap without need for an upgrade func

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skilesare February 2, 2023, 3:51pm 9

@ZhenyaUsenko Maybe we should add mops support to this library?

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Stable HashMap without need for an upgrade func

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