The following shouldn't be possible.

{"@set": 1, "val": 1}

Figure for quote_close should be different from quote_start

Given a dictionary {name: "bob", age: 19}

A particular key may be changed,

{"@set": "person", "key": "`age`", "val": 20}

support namespace so that variables and functions imported from other components with use statement does not conflict with symbols defined in the current component

Def statement should be reclassified as non-terminal from terminal