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> locals can no longer be used before declaration

There's a lot I like about Lua but it so happens that a few days ago I spent longer than I'd like to admit debugging a trivial typo for Advent of Code day 5 that would have been caught by this.

Wondering if Luon will also prohibit or at least warn about storing nil in a table.

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Luon doesn't directly support tables, but instead supports records, arrays and hashmaps (which internally use tables). Since it's statically typed you can only store nil to a field or element if it is of a structured type.

What's a structured type? Something that has fields or elements?

Records, arrays and hashmaps are structured types; in contrast to original Oberon, Luon has no pointer type, but reference semantics instead.

So Luon has reference types and value types, and reference types are always nullable?

Yes, but value types are only basic types. Structured types only have reference semantics and are nil by default.

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