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#[cfg(test)]
extern crate quickcheck;
#[cfg(test)]
#[macro_use(quickcheck)]
extern crate quickcheck_macros;

#[macro_use]
pub mod util;
pub mod mp;

use bellperson::SynthesisError;
use ff::PrimeField;

trait OptionExt<T> {
    fn grab(&self) -> Result<&T, SynthesisError>;
    fn grab_mut(&mut self) -> Result<&mut T, SynthesisError>;
}

impl<T> OptionExt<T> for Option<T> {
    fn grab(&self) -> Result<&T, SynthesisError> {
        self.as_ref().ok_or(SynthesisError::AssignmentMissing)
    }
    fn grab_mut(&mut self) -> Result<&mut T, SynthesisError> {
        self.as_mut().ok_or(SynthesisError::AssignmentMissing)
    }
}

trait BitAccess {
    fn get_bit(&self, i: usize) -> Option<bool>;
}

impl<Scalar: PrimeField> BitAccess for Scalar {
    fn get_bit(&self, i: usize) -> Option<bool> {
        if i as u32 >= Scalar::NUM_BITS {
            return None;
        }

        let (byte_pos, bit_pos) = (i / 8, i % 8);
        let byte = self.to_repr().as_ref()[byte_pos];
        let bit = byte >> bit_pos & 1;
        Some(bit == 1)
    }
}