A partial solution to the problem posed here: https://twitter.com/mikelikesbikes/status/1396159019837018117
This solution represents the expressions in reverse Polish notation (RPN) - see also Forth and HP48s.
The version presented here does NOT produce all values from 1 to 100, as it does not use enough operators.
Extending the search to additional operators only requires adding the value to @operators
and a clause to eval
to handle it.