# [Community Puzzle] Propositions in Frege’s ideography

Maybe your answer is not lexicographically sorted, or you missed a case.

For

`[(C and B) implies A] implies [(C implies B) implies A]`

ASCII should be:

Thanks! Found an issue. Dumb one. My code is a bit over complicated, so

I don’t know if this is too picky or not but I would have liked at least 1 test case with multiple violations that way the output could be tested properly.

Do you have an example?

I was thinking about two specific behaviors but I went back and in fairness, they are both discussed in the problem statement so I jumped the gun there.

I was thinking of

1. A “not” (’+’) occurring before a branch, which is addressed in the problem statement as:

±-- A
’ – B

1. A multiple line output, which is also addressed at the end of the problem statement.

Its a good problem, I enjoyed doing it, I did have to come to the discussions page to figure out why I was failing a validator and not any test cases was all.

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About your second point, I permuted the last couple of test and validator.
About your first point, the A nor B validator starts with a +. I inserted a test and a validator for nor.

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A implies B equals ((not A) or B) is correct but it implies one more condition that’s important to account for: A false and B false evaluates to true also. This is the truth table for implies statements:

``````       |B false|B true
-----------------------
A false|true   |true
A true |false  |true
``````