- Add function calls to expressions. For now only hard-coded functions such as MIN and MAX should be added.
- Add bank number to label struct
- Add a BANKNUM function e.g. BANKNUM(label)
-- Add stack-machine based expressions (e.g. 1 2 +, 1 2 max). keep previous expression syntax but deprecate it. denote stack expressions with a prefix like % (e.g. ld a, % 1 2 max).
+- Add stack-machine based expressions (e.g. 1 2 +, 1 2 max). keep previous expression syntax but deprecate it. switch expression mode syntax with a directive e.g. .smon and .smoff (stack machine on/off).