Prove some remaining admitted lemmas in a slightly silly way#28
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voiestad
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Looks good to me🐔
I think it's best to keep the string_of_int_length_4 admitted. No need to add 10k lines to the code base.
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This more or less proves the remaining lemmas in
Grammar.v, so that e.g.ISODateTimeToStringis basically proven to be RFC3339 compliant. Yay!The remaining lemmas were basically just of the form "an integer between 0 and 99 is a most two digits long." The proof is by exhaustion, which leads to a caveat:
string_of_int_length_4, which is for integers between 0 and 9999, is still admitted. That's because the generated ten-thousand line proof took longer to compile than the rest of the project combined. But it does check, so the lemma is in fact correct (if you trust me). I can add this proof back if it is desirable to have.