Traceback:
in
NameError: name 'Alphabet' is not defined

For python, I cannot run the tests.

@nklein: making it clear on the description the expected order of operations should solve this issue.

I think there's a bug on the test case.

For:

[ x y z ] ( 23x + 5y - 3z ) / (1 + 3 + 2*2)

This is also valid for pass1:

{"op":"/","a":{"op":"+","a":{"op":"","a":{"op":"imm","n":2},"b":{"op":"","a":{"op":"imm","n":3},"b":{"op":"arg","n":0}}},"b":{"op":"-","a":{"op":"","a":{"op":"imm","n":5},"b":{"op":"arg","n":1}},"b":{"op":"","a":{"op":"imm","n":3},"b":{"op":"arg","n":2}}}},"b":{"op":"+","a":{"op":"imm","n":1},"b":{"op":"+","a":{"op":"imm","n":3},"b":{"op":"*","a":{"op":"imm","n":2},"b":{"op":"imm","n":2}}}}}

I didn't quite where does the ideam sum/ ideal product comes from?