> What LispE proposes is to turn each instruction of the language into a derived class that exposes an eval method. Every class has its own override of eval. And since all these classes derive from a single mother class with an original and evocative name, Element, you can build a C++ vector that holds them all. And that is where the miracle happens: the AST is kept alive, but each node is an object that can be optimized to the hilt with the full C++ arsenal.That's... a tree-walking interpreter. And IIRC the most overhead of it comes from traversing the tree itself, then from the overhead of invoking (virtual) eval() methods, and only then from whatever inefficiencies are inside of those tiny eval() implementations.
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