1use algebra::Field;
  2use r1cs_core::{ConstraintSystem, SynthesisError};
  3use std::borrow::Borrow;
  4
  5pub trait AllocGadget<V, ConstraintF: Field>
  6where
  7    Self: Sized,
  8    V: ?Sized,
  9{
 10    fn alloc<F, T, CS: ConstraintSystem<ConstraintF>>(cs: CS, f: F) -> Result<Self, SynthesisError>
 11    where
 12        F: FnOnce() -> Result<T, SynthesisError>,
 13        T: Borrow<V>;
 14
 15    fn alloc_checked<F, T, CS: ConstraintSystem<ConstraintF>>(cs: CS, f: F) -> Result<Self, SynthesisError>
 16    where
 17        F: FnOnce() -> Result<T, SynthesisError>,
 18        T: Borrow<V>,
 19    {
 20        Self::alloc(cs, f)
 21    }
 22
 23    fn alloc_input<F, T, CS: ConstraintSystem<ConstraintF>>(cs: CS, f: F) -> Result<Self, SynthesisError>
 24    where
 25        F: FnOnce() -> Result<T, SynthesisError>,
 26        T: Borrow<V>;
 27
 28    fn alloc_input_checked<F, T, CS: ConstraintSystem<ConstraintF>>(
 29        cs: CS,
 30        f: F,
 31    ) -> Result<Self, SynthesisError>
 32    where
 33        F: FnOnce() -> Result<T, SynthesisError>,
 34        T: Borrow<V>,
 35    {
 36        Self::alloc_input(cs, f)
 37    }
 38}
 39
 40impl<I, ConstraintF: Field, A: AllocGadget<I, ConstraintF>> AllocGadget<[I], ConstraintF> for Vec<A> {
 41    fn alloc<F, T, CS: ConstraintSystem<ConstraintF>>(mut cs: CS, f: F) -> Result<Self, SynthesisError>
 42    where
 43        F: FnOnce() -> Result<T, SynthesisError>,
 44        T: Borrow<[I]>,
 45    {
 46        let mut vec = Vec::new();
 47        for (i, value) in f()?.borrow().iter().enumerate() {
 48            vec.push(A::alloc(&mut cs.ns(|| format!("value_{}", i)), || {
 49                Ok(value)
 50            })?);
 51        }
 52        Ok(vec)
 53    }
 54
 55    fn alloc_input<F, T, CS: ConstraintSystem<ConstraintF>>(mut cs: CS, f: F) -> Result<Self, SynthesisError>
 56    where
 57        F: FnOnce() -> Result<T, SynthesisError>,
 58        T: Borrow<[I]>,
 59    {
 60        let mut vec = Vec::new();
 61        for (i, value) in f()?.borrow().iter().enumerate() {
 62            vec.push(A::alloc_input(
 63                &mut cs.ns(|| format!("value_{}", i)),
 64                || Ok(value),
 65            )?);
 66        }
 67        Ok(vec)
 68    }
 69
 70    fn alloc_checked<F, T, CS: ConstraintSystem<ConstraintF>>(
 71        mut cs: CS,
 72        f: F,
 73    ) -> Result<Self, SynthesisError>
 74    where
 75        F: FnOnce() -> Result<T, SynthesisError>,
 76        T: Borrow<[I]>,
 77    {
 78        let mut vec = Vec::new();
 79        for (i, value) in f()?.borrow().iter().enumerate() {
 80            vec.push(A::alloc_checked(
 81                &mut cs.ns(|| format!("value_{}", i)),
 82                || Ok(value),
 83            )?);
 84        }
 85        Ok(vec)
 86    }
 87
 88    fn alloc_input_checked<F, T, CS: ConstraintSystem<ConstraintF>>(
 89        mut cs: CS,
 90        f: F,
 91    ) -> Result<Self, SynthesisError>
 92    where
 93        F: FnOnce() -> Result<T, SynthesisError>,
 94        T: Borrow<[I]>,
 95    {
 96        let mut vec = Vec::new();
 97        for (i, value) in f()?.borrow().iter().enumerate() {
 98            vec.push(A::alloc_input_checked(
 99                &mut cs.ns(|| format!("value_{}", i)),
100                || Ok(value),
101            )?);
102        }
103        Ok(vec)
104    }
105}