WIP: initial ast for program, comment, variable, reassignment

[jschatz1]

Initial AST for program, comments, variable declarations, and variable reassignment.

[jschatz1]

One thing I am not sure of is if "everything is a function" in foi or not. @getify what's your thoughts?

[getify]

@jschatz1

No, not everything is a function.

For example, empty, import, def, deft, defn, over, as, and default are all keywords. We also values, like numbers and strings, as well as records and tuples, and those are all definitely not functions.

However, all operators are functions, and most non-identifier symbols are operators/functions. For example, the . looks like it might be a special syntax, but it's actually a binary accessor-operator, so x.1 can also be done as | . x 1 |. Same with the .. tuple-range operator and the ... spread operator.

Exceptions: the ; and : separators, the , comma (list separator), sigils like ^ (return) / & (pick) / % (map-field), the # pipeline topic / def-block context, the -> function-return-type marker, and several sets of paired delimiters like " double-quotes (string delimiters), | | evaluation-expression (lisp) form, < and > record/tuple delimiters, <{ }>, { }, [ ], ( ), ?/ /, etc.