BIP 0340 followups #253
BIP 0340 followups #253
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apoelstra
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| let err = ffi::secp256k1_xonly_pubkey_tweak_add_check( | ||
| secp.ctx, | ||
| tweaked_ser.as_c_ptr(), | ||
| if tweaked_parity { 1 } else { 0 }, |
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You can do tweaked_parity as u8
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Oh nice. Though I'd have to cast to a c_int ... with the export, the if statement is actually shorter, and in any case it's more explicit.
src/schnorrsig.rs
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| secp.ctx, | ||
| tweaked_ser.as_c_ptr(), | ||
| if tweaked_parity { 1 } else { 0 }, | ||
| &self.0 as *const _, |
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Can you replace with self.0.as_c_ptr()?
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I don't think so, this is a FFI type not a byte array
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References coerce to pointers, so you wouldn't actually need the cast: &self.0.
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lol I had no idea. Added a commit which fixes this across the library.
src/schnorrsig.rs
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| tweaked_key: &Self, | ||
| tweaked_parity: bool, | ||
| tweak: &[u8], | ||
| ) -> Result<(), Error> { |
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What do you think about passing tweak: [u8; 32] and then returning bool instead of a Result?
In general I feel like it would be nicer to use the type system to require sizes instead of adding dozens of results/errors (especially with TryFrom that let's you slice.try_into()? for converting to array, but that's 1.34)
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if for ergonomic pre 1.34 reasons you want to keep it as a slice then that's ok
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Yeah I think it'd be reasonable to use arrays here.
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Welll, for what it's worth we already have an error return here if the user passes an invalid tweak. If you know you're giving a hash then it can't fail, but that's still an error you have to .unwrap away.
I'm not sure there's any additonal ergonomics loss to using a slice.
Couple things on #237 that weren't done in the original PR.