• Each idiom gets a public and a private wordlist
• Each idiom includes its parents' public words and all of its parents' parents' public words.
• Private words are available only to the current idiom they are defined in. (for now)
• On top of that, idioms can "import" the public wordlists of other idioms.
• When executed, an idiom word will rewrite the search order and make the current defining wordlist the public wordlist.
• Switch between defining public and private words with _public and _private (the underscores are to avoid conflicts with legacy SwiftForth code)
• Public and private wordlists can be "exported" for special cases.
• TODO: Enforcing loading of parent idioms only once, for modules of that kind