Hey guys, I used HashMap before. Now I want to use preupgrade and postupgrade to copy the data in userMap to userTrie. I found that Inter has a toList function and Trie has fromList function. Does anyone know how to use these two functions? Or is there any other way? thx. var userMap = HashMap.Has…

Thanks to everyone, the problem is solved, here is the solution, I hope to help others in the future. step1: Add an array: stable var userEntries: [(Text, Text)] = []; In preupgrade(), copy the data of userMap to userEntries system func preupgrade() { userEntries := Iter.toArray(userMap.entr…

How to use preupgrade and postupgrade to upgrade HashMap to Trie

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peterparker October 12, 2021, 2:58pm 3

Any particular reason to use a Trie instead of an Array (as discussed / displayed here) as stable memory to process the upgrade?

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How to use preupgrade and postupgrade to upgrade HashMap to Trie

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