Add "maybeHeap" utility function.
Add commetns
Update syntax for mutable arrays.
Evaluate collection expressions.
Evaluate LoadElement expressions.
Start adding type checking (work in progress).
Add "mand" utility function.
Add logic for recognizing subclasses (work in progress).
Add spawn and wait commands.
Add missing pattern for "show" function.
Add missing case for "isSubclass" function.
Check the return value after each function call.
Check the return value of each "wait" instruction.
Add type annotation.
Evaluate cast expressions.
Start implementing simple operations.