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So, I'm working on compiling @_ohmjs grammars to Wasm. _Recognition_ (does this text match or not) wasn't too bad, and this week I've been working on building parse trees. I'm doing manual memory mgmt (simple bump pointer). This code deals with repetition, which is tricky… 2/x

For many nodes, we know how many children there will be, so we can allocate the correct amount of space directly in the parent node. This is conceptually simple, and cache-friendly too. 3/x

But an iteration node can have any # of children! So when the parent node is allocated, we don't know how big to make it. My solution: • Allocate space for a fixed (power of 2) # of children • If necessary, use the last child slot to point to an overflow node. 4/x