A flaw with the JSON model is that there is no inherent sorting to the order of pairs. This has problems for canonicalisation, but also for shadowing. A Lisp

A flaw with the JSON model is that there is no inherent sorting to the order of pairs. This has problems for canonicalisation, but also for shadowing. A Lisp can use an alist to represent a set of key-value pairs, and is easy enough to shadow values there: (defvar original '((a . 1) (b . 2))) → ((A . 1) (B . 2)) (assoc 'b foo) → (B . 2) (defvar bar `((b . 3) ,@foo)) → ((B . 3) (A . 1) (B . 2)) (assoc 'b bar) → (B . 3) This makes it easy to implement things like inheritance or trees of lexical environments. I sometimes wish that Lisp had better ergonomics for hash tables, but normally I am pretty happy that folks don't reach for them first. Frankly, I think positionality is normally good. Can you image how terrible it would be to program a language in which addition is represented as: add(operand: 1, operand: 2)