wo / tpg

Tree Proof Generator
GNU General Public License v3.0
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pv¬p doesn't work #7

Closed falvear210 closed 3 years ago

falvear210 commented 3 years ago

The formula pv¬p does not work. The error says: "I don't understand '¬' in 'pv¬p'. Missing operator?" Tried with (p)v(¬p), pv(¬p), and (pv(¬p)) with no success.

falvear210 commented 3 years ago

The formula pv¬p does not work. The error says: "I don't understand '¬' in 'pv¬p'. Missing operator?" Tried with (p)v(¬p), pv(¬p), and (pv(¬p)) with no success.

Strangely, the formulas previously mentioned work in iOS Chrome but not in macOS Chrome or Safari

wo commented 3 years ago

Thanks. The problem is that the letter 'v' is often used as a variable, e.g. in 'Fvw'. Compare 'p -> (qvr)' and 'Fa -> (Gavr)'. In the first sentence, 'v' is probably meant as disjunction, in the second it might be meant as disjunction but it might equally be meant as a singular term. I've settled on reading 'v' as disjunction only if there's a space on either side. This is now mentioned in the error message.

falvear210 commented 3 years ago

Thank you! This is an awesome tool btw, very well executed!