I'm not sure if you mean in JS or in CL, but it works basically the same way: deserialize it (not eval) and walk through the array, doing the exact same kind of steps they're doing in the article for the JS version. Build up a symbol table (or two, if your function names and variable names are in different namespaces). The evaluation rules are so simple and consistent that the logic required while walking the array is pretty tiny.
To do the same thing with Javascript code involves parsing into an AST and walking the that tree; the hard part is that the rules for walking that tree are dramatically more complicated. In the Lisp case, the AST and the original code look very similar; in the JS case, they diverge quite a bit (there's a ton of crazy things in the JS spec if you dig through it)
To do the same thing with Javascript code involves parsing into an AST and walking the that tree; the hard part is that the rules for walking that tree are dramatically more complicated. In the Lisp case, the AST and the original code look very similar; in the JS case, they diverge quite a bit (there's a ton of crazy things in the JS spec if you dig through it)