It's not clear to me how function privacy is achieved. Slide 7 says "The transaction proof now checks that the predicate ... is satisfied". From my understanding of ZKP, in order to verify the proof, the verifier needs to know the predicate function to obtain the verification key (assuming SNARKS is used), which means the predicate function can't be hidden from the verifiers. Could anyone clarify this for me? Thanks in advance!
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It's not clear to me how function privacy is achieved. Slide 7 says "The transaction proof now checks that the predicate ... is satisfied". From my understanding of ZKP, in order to verify the proof, the verifier needs to know the predicate function to obtain the verification key (assuming SNARKS is used), which means the predicate function can't be hidden from the verifiers. Could anyone clarify this for me? Thanks in advance!