While testing a calculation with multiple modifiers I came across what appears to be a problem.
The table above is merely a simplification to show the issue
A human expects the answer to be 75
IPP returns 85
The human works from the left .. 100 - 20 = 80 ... 80-5 = 75
IPP apparently works from the right ... 20-5 = 15 ... 100-15 = 85
I suspect the syntactical grammar for the language used in IPP (which I would love to see by the way) ... has a problem with left associativity (probably indirect left recursion)
Oh and I am aware that I can use brackets to change the order of precedence as a work around (and have done), I merely wanted to highlight the problem as a bug.