fix type => [value|element]_type
Clean up style violations
Flatten/unfill applications and builtins when encoding
Remove multi-argument applications
They only exist in binary encoding, so let's keep them there.
Every AST node uses as_json to express the generic structure for
encoding itself. Expression aliases as_cbor to as_json by default and
then uses as_cbor in to_cbor (aliased as to_binary).
This design is because we need to override the encoding of Double for
CBOR, but want to keep the normal Float value for as_json in case that
is used directly (to avoid surprising the user).
Make every Expression a ValueSemantics and use the known list of
attributes to map generically over any AST node.
Introduces a conditional, but removes boilerplate from every single
Bare minimum refactor to pass the metrics
Pass most compliance tests
No import or multiline string support yet
Beta normalization complete
All beta normalization except for functions
Implement many builtins and do Optional section