mul

src/bigint.rs

@@ -0,0 +1,83 @@
+#![cfg(feature = "num-bigint")]
+
+use num_bigint::BigInt;
+use num_bigint::BigUint;
+use num_bigint::Sign;
+
+use core::mem::ManuallyDrop;
+
+use crate::SmallInt;
+use crate::SmallUint;
+
+use crate::smallint::SmallIntType;
+use crate::smallint::SmallUintType;
+
+impl From<&BigInt> for SmallInt {
+    fn from(b: &BigInt) -> Self {
+        match b.try_into() {
+            Ok(i) => Self(SmallIntType::Inline(i)),
+            Err(_) => {
+                let (sign, vec) = b.to_u32_digits();
+                let mut slice = ManuallyDrop::new(vec.into_boxed_slice());
+                let size = match sign {
+                    Sign::Minus => -isize::try_from(slice.len()).unwrap(),
+                    Sign::NoSign => panic!(
+                        "Shouldn't happen; BigInts which store zero should convert to inline."
+                    ),
+                    Sign::Plus => isize::try_from(slice.len()).unwrap(),
+                };
+                Self(SmallIntType::Heap((slice.as_mut_ptr(), size)))
+            }
+        }
+    }
+}
+
+impl From<&SmallInt> for BigInt {
+    fn from(s: &SmallInt) -> Self {
+        match s.0 {
+            SmallIntType::Inline(i) => Self::from(i),
+            SmallIntType::Heap((r, s)) => {
+                let size = usize::try_from(s.abs()).unwrap();
+                let sign = s.signum();
+                let slice = unsafe { core::slice::from_raw_parts(r, size) };
+                let bs = match sign {
+                    0 => Sign::NoSign,
+                    -1 => Sign::Minus,
+                    1 => Sign::Plus,
+                    _ => panic!("This shouldn't happen; There are only 3 signums."),
+                };
+
+                BigInt::new(bs, slice.to_vec())
+            }
+        }
+    }
+}
+
+impl From<&BigUint> for SmallUint {
+    fn from(b: &BigUint) -> Self {
+        match b.try_into() {
+            Ok(i) => Self(SmallUintType::Inline(i)),
+            Err(_) => {
+                let vec = b.to_u32_digits();
+                let mut slice = ManuallyDrop::new(vec.into_boxed_slice());
+                let size = slice.len();
+                Self(SmallUintType::Heap((slice.as_mut_ptr(), size)))
+            }
+        }
+    }
+}
+
+impl From<&SmallUint> for BigUint {
+    fn from(s: &SmallUint) -> Self {
+        match s.0 {
+            SmallUintType::Inline(i) => Self::from(i),
+            SmallUintType::Heap((r, s)) => {
+                let slice = unsafe { core::slice::from_raw_parts(r, s) };
+
+                BigUint::new(slice.to_vec())
+            }
+        }
+    }
+}
+
+

src/convert.rs

@@ -0,0 +1,155 @@
+use crate::SmallInt;
+use crate::SmallUint;
+use crate::SmallIntError;
+use crate::smallint::{SmallIntType, SmallUintType};
+use core::mem::ManuallyDrop;
+
+macro_rules! int_impl {
+    ($itype:ty, $rt:tt, $rtt:tt, $n:tt) => {
+        impl From<$itype> for $rt {
+            fn from(a: $itype) -> Self {
+                Self(<$rtt>::Inline($n::from(a)))
+            }
+        }
+
+        impl TryFrom<$rt> for $itype {
+            type Error = SmallIntError;
+
+            fn try_from(s: $rt) -> Result<Self, Self::Error> {
+                match s.0 {
+                    $rtt::Inline(i) => {
+                        <$itype>::try_from(i).map_err(|_| SmallIntError::ConversionError)
+                    }
+                    $rtt::Heap((_, _)) => Err(SmallIntError::ConversionError),
+                }
+            }
+        }
+    };
+}
+
+int_impl!(u8, SmallInt, SmallIntType, i128);
+int_impl!(u16, SmallInt, SmallIntType, i128);
+int_impl!(u32, SmallInt, SmallIntType, i128);
+int_impl!(u64, SmallInt, SmallIntType, i128);
+int_impl!(i8, SmallInt, SmallIntType, i128);
+int_impl!(i16, SmallInt, SmallIntType, i128);
+int_impl!(i32, SmallInt, SmallIntType, i128);
+int_impl!(i64, SmallInt, SmallIntType, i128);
+int_impl!(i128, SmallInt, SmallIntType, i128);
+
+int_impl!(u8, SmallUint, SmallUintType, u128);
+int_impl!(u16, SmallUint, SmallUintType, u128);
+int_impl!(u32, SmallUint, SmallUintType, u128);
+int_impl!(u64, SmallUint, SmallUintType, u128);
+int_impl!(u128, SmallUint, SmallUintType, u128);
+
+macro_rules! try_from_itou {
+    ($itype:ty) => {
+        impl TryFrom<$itype> for SmallUint {
+            type Error = SmallIntError;
+
+            fn try_from(a: $itype) -> Result<Self, Self::Error> {
+                Ok(Self(SmallUintType::Inline(
+                    u128::try_from(a).map_err(|_| SmallIntError::ConversionError)?,
+                )))
+            }
+        }
+
+        impl TryFrom<SmallUint> for $itype {
+            type Error = SmallIntError;
+
+            fn try_from(s: SmallUint) -> Result<Self, Self::Error> {
+                match s.0 {
+                    SmallUintType::Inline(i) => {
+                        <$itype>::try_from(i).map_err(|_| SmallIntError::ConversionError)
+                    }
+                    SmallUintType::Heap((_, _)) => Err(SmallIntError::ConversionError),
+                }
+            }
+        }
+    };
+}
+
+try_from_itou!(i8);
+try_from_itou!(i16);
+try_from_itou!(i32);
+try_from_itou!(i64);
+try_from_itou!(i128);
+
+impl From<u128> for SmallInt {
+    fn from(a: u128) -> Self {
+        match i128::try_from(a) {
+            Ok(i) => Self(SmallIntType::Inline(i)),
+            Err(_) => {
+                let mut v = a;
+                let mut vec = Vec::with_capacity(4);
+                while v != 0 {
+                    vec.push(v as u32);
+
+                    v >>= 32;
+                }
+                let mut slice = ManuallyDrop::new(vec.into_boxed_slice());
+                Self(SmallIntType::Heap((
+                    slice.as_mut_ptr(),
+                    isize::try_from(slice.len()).unwrap(),
+                )))
+            }
+        }
+    }
+}
+
+impl TryFrom<SmallInt> for u128 {
+    type Error = SmallIntError;
+
+    fn try_from(s: SmallInt) -> Result<Self, Self::Error> {
+        match s.0 {
+            SmallIntType::Inline(i) => {
+                u128::try_from(i).map_err(|_| SmallIntError::ConversionError)
+            }
+            SmallIntType::Heap((r, s)) => {
+                let mut ret: u128 = 0;
+                let mut bits = 0;
+                let size = usize::try_from(s.abs()).unwrap();
+                let slice = unsafe { core::slice::from_raw_parts(r, size) };
+                for i in slice {
+                    if bits >= 128 {
+                        return Err(SmallIntError::ConversionError);
+                    }
+                    ret |= u128::from(*i) << bits;
+                    bits += 32;
+                }
+
+                Ok(ret)
+            }
+        }
+    }
+}
+
+impl From<SmallUint> for SmallInt {
+    fn from(s: SmallUint) -> Self {
+        match s.0 {
+            SmallUintType::Inline(i) => SmallInt::from(i),
+            SmallUintType::Heap((r, s)) => {
+                SmallInt(SmallIntType::Heap((r, isize::try_from(s).unwrap())))
+            }
+        }
+    }
+}
+
+impl TryFrom<SmallInt> for SmallUint {
+    type Error = SmallIntError;
+
+    fn try_from(value: SmallInt) -> Result<Self, Self::Error> {
+        match value.0 {
+            SmallIntType::Inline(i) => Self::try_from(i),
+            SmallIntType::Heap((r, s)) => {
+                let size = usize::try_from(s).map_err(|_| SmallIntError::ConversionError)?;
+                if size > 4 {
+                    Ok(Self(SmallUintType::Heap((r, size))))
+                } else {
+                    Ok(Self(SmallUintType::Inline(u128::try_from(value)?)))
+                }
+            }
+        }
+    }
+}

src/error.rs

@@ -0,0 +1,15 @@
+/// An error that occurred when processing a `SmallInt`.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum SmallIntError {
+    /// Conversion error when converting from SmallInt to other integer types.
+    ConversionError,
+}
+
+impl std::error::Error for SmallIntError {}
+
+impl core::fmt::Display for SmallIntError {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        let Self::ConversionError = self;
+        write!(f, "Error converting integer to SmallInt.")
+    }
+}

src/lib.rs

@@ -9,473 +9,20 @@
 // Invariant: If a small integer is on the heap, the size is the minimum digits required to
 // represent it.
 
-#[cfg(feature = "num-bigint")]
+mod smallint;
-use num_bigint::BigInt;
 
-#[cfg(feature = "num-bigint")]
+pub use crate::smallint::SmallInt;
-use num_bigint::BigUint;
+pub use crate::smallint::SmallUint;
 
-#[cfg(feature = "num-bigint")]
+mod error;
-use num_bigint::Sign;
 
-use core::mem::ManuallyDrop;
+pub use error::SmallIntError;
-use core::ops::Add;
 
-/// An error that occurred when processing a `SmallInt`.
+mod convert;
-#[derive(Debug, Clone, PartialEq, Eq)]
+mod ops;
-pub enum SmallIntError {
-    /// Conversion error when converting from SmallInt to other integer types.
-    ConversionError,
-}
 
-impl std::error::Error for SmallIntError {}
+mod bigint;
 
-impl core::fmt::Display for SmallIntError {
+mod pretty;
-    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
-        let Self::ConversionError = self;
-        write!(f, "Error converting integer to SmallInt.")
-    }
-}
 
-/// An integer-like type that will store small integers up to `i128` inline. Larger integers are
+mod tests;
-/// represented as a slice to a sequence of base 2<sup>32</sup> digits represented as a `*mut u32`.
-#[derive(Clone, PartialEq, Eq)]
-pub struct SmallInt(SmallIntType);
-
-/// An integer-like type that will store small integers up to `u128` inline. Larger integers are
-/// represented as a slice to a sequence of base 2<sup>32</sup> digits represented as a `*mut u32`.
-#[derive(Clone, PartialEq, Eq)]
-pub struct SmallUint(SmallUintType);
-
-#[derive(Clone, PartialEq, Eq)]
-enum SmallIntType {
-    Inline(i128),
-    Heap((*mut u32, isize)),
-}
-
-#[derive(Clone, PartialEq, Eq)]
-enum SmallUintType {
-    Inline(u128),
-    Heap((*mut u32, usize)),
-}
-
-// TODO: Need to reimplement Debug, to_str_radix, and from_str_radix without num-bigint feature for
-// SmallInt and SmallUint
-
-// TODO: add native operations for SmallInt and SmallUint
-
-#[cfg(feature = "num-bigint")]
-impl core::fmt::Debug for SmallInt {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{}", BigInt::from(self))
-    }
-}
-
-#[cfg(feature = "num-bigint")]
-impl core::fmt::Debug for SmallUint {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{}", BigUint::from(self))
-    }
-}
-
-fn add_two_slices(slice1: &[u32], slice2: &[u32]) -> Vec<u32> {
-
-    let s = slice1.len();
-    let j = slice2.len();
-
-    let larger = std::cmp::max(s, j);
-    let mut res = Vec::with_capacity(larger + 1);
-    let mut carry = false;
-
-    for t in 0..larger {
-
-        let value1 = if t < s {
-            slice1[t]
-        } else {
-            0
-        };
-
-        let value2 = if t < j {
-            slice2[t]
-        } else {
-            0
-        };
-
-        let (val, overflow) = value1.overflowing_add(value2);
-        let (cval, coverflow) = val.overflowing_add(carry as u32);
-        res.push(cval);
-        carry = overflow | coverflow;
-
-    }
-
-    if carry {
-        res.push(1);
-    }
-    while res[res.len() - 1] == 0 {
-        res.pop();
-    }
-    res
-}
-
-impl Add<SmallUint> for SmallUint {
-    type Output = SmallUint;
-
-    fn add(self, rhs: SmallUint) -> Self::Output {
-        match (&self.0, &rhs.0) {
-            (&SmallUintType::Inline(i), &SmallUintType::Inline(j)) => {
-                match i.overflowing_add(j) {
-                    (t, false) => Self(SmallUintType::Inline(t)),
-                    (t, true) => {
-
-
-                        let mut res = [0, 0, 0, 0, 1];
-
-                        let mut v = t;
-                        #[allow(clippy::needless_range_loop)]
-                        for r in 0..4 {
-                            res[r] = v as u32;
-
-                            v >>= 32;
-                        }
-
-                        Self(SmallUintType::Heap((<Box<[u32]>>::from(res).as_mut_ptr(), 5)))
-
-                    }
-                }
-            },
-            (&SmallUintType::Heap((r, s)), &SmallUintType::Inline(i)) | (&SmallUintType::Inline(i), &SmallUintType::Heap((r, s))) => {
-                let slice1 = unsafe { core::slice::from_raw_parts(r, s) };
-
-                let mut res = [0, 0, 0, 0, 1];
-
-                let mut v = i;
-                #[allow(clippy::needless_range_loop)]
-                for r in 0..4 {
-                    res[r] = v as u32;
-
-                    v >>= 32;
-                }
-                let result = add_two_slices(slice1, &res[..]);
-                let size = result.len();
-
-                let mut slice = ManuallyDrop::new(result.into_boxed_slice());
-
-                Self(SmallUintType::Heap((slice.as_mut_ptr(), size)))
-
-
-            },
-            (&SmallUintType::Heap((r, s)), &SmallUintType::Heap((i, j))) => {
-
-                let slice1 = unsafe { core::slice::from_raw_parts(r, s) };
-                let slice2 = unsafe { core::slice::from_raw_parts(i, j) };
-
-                let res = add_two_slices(slice1, slice2);
-                let size = res.len();
-
-                let mut slice = ManuallyDrop::new(res.into_boxed_slice());
-
-                Self(SmallUintType::Heap((slice.as_mut_ptr(), size)))
-
-            }
-        }
-    }
-}
-
-impl Drop for SmallInt {
-    fn drop(&mut self) {
-        if let Self(SmallIntType::Heap((r, s))) = self {
-            let size = usize::try_from(s.abs()).unwrap();
-            let slice = unsafe { core::slice::from_raw_parts_mut(*r, size) };
-            unsafe { std::mem::drop(Box::from_raw(slice)) }
-        }
-    }
-}
-
-impl Drop for SmallUint {
-    fn drop(&mut self) {
-        if let Self(SmallUintType::Heap((r, s))) = self {
-            let slice = unsafe { core::slice::from_raw_parts_mut(*r, *s) };
-            unsafe { std::mem::drop(Box::from_raw(slice)) }
-        }
-    }
-}
-
-macro_rules! int_impl {
-    ($itype:ty, $rt:tt, $rtt:tt, $n:tt) => {
-        impl From<$itype> for $rt {
-            fn from(a: $itype) -> Self {
-                Self(<$rtt>::Inline($n::from(a)))
-            }
-        }
-
-        impl TryFrom<$rt> for $itype {
-            type Error = SmallIntError;
-
-            fn try_from(s: $rt) -> Result<Self, Self::Error> {
-                match s.0 {
-                    $rtt::Inline(i) => {
-                        <$itype>::try_from(i).map_err(|_| SmallIntError::ConversionError)
-                    }
-                    $rtt::Heap((_, _)) => Err(SmallIntError::ConversionError),
-                }
-            }
-        }
-    };
-}
-
-int_impl!(u8, SmallInt, SmallIntType, i128);
-int_impl!(u16, SmallInt, SmallIntType, i128);
-int_impl!(u32, SmallInt, SmallIntType, i128);
-int_impl!(u64, SmallInt, SmallIntType, i128);
-int_impl!(i8, SmallInt, SmallIntType, i128);
-int_impl!(i16, SmallInt, SmallIntType, i128);
-int_impl!(i32, SmallInt, SmallIntType, i128);
-int_impl!(i64, SmallInt, SmallIntType, i128);
-int_impl!(i128, SmallInt, SmallIntType, i128);
-
-int_impl!(u8, SmallUint, SmallUintType, u128);
-int_impl!(u16, SmallUint, SmallUintType, u128);
-int_impl!(u32, SmallUint, SmallUintType, u128);
-int_impl!(u64, SmallUint, SmallUintType, u128);
-int_impl!(u128, SmallUint, SmallUintType, u128);
-
-macro_rules! try_from_itou {
-    ($itype:ty) => {
-        impl TryFrom<$itype> for SmallUint {
-            type Error = SmallIntError;
-
-            fn try_from(a: $itype) -> Result<Self, Self::Error> {
-                Ok(Self(SmallUintType::Inline(
-                    u128::try_from(a).map_err(|_| SmallIntError::ConversionError)?,
-                )))
-            }
-        }
-
-        impl TryFrom<SmallUint> for $itype {
-            type Error = SmallIntError;
-
-            fn try_from(s: SmallUint) -> Result<Self, Self::Error> {
-                match s.0 {
-                    SmallUintType::Inline(i) => {
-                        <$itype>::try_from(i).map_err(|_| SmallIntError::ConversionError)
-                    }
-                    SmallUintType::Heap((_, _)) => Err(SmallIntError::ConversionError),
-                }
-            }
-        }
-    };
-}
-
-try_from_itou!(i8);
-try_from_itou!(i16);
-try_from_itou!(i32);
-try_from_itou!(i64);
-try_from_itou!(i128);
-
-impl From<u128> for SmallInt {
-    fn from(a: u128) -> Self {
-        match i128::try_from(a) {
-            Ok(i) => Self(SmallIntType::Inline(i)),
-            Err(_) => {
-                let mut v = a;
-                let mut vec = Vec::with_capacity(4);
-                while v != 0 {
-                    vec.push(v as u32);
-
-                    v >>= 32;
-                }
-                let mut slice = ManuallyDrop::new(vec.into_boxed_slice());
-                Self(SmallIntType::Heap((
-                    slice.as_mut_ptr(),
-                    isize::try_from(slice.len()).unwrap(),
-                )))
-            }
-        }
-    }
-}
-
-impl TryFrom<SmallInt> for u128 {
-    type Error = SmallIntError;
-
-    fn try_from(s: SmallInt) -> Result<Self, Self::Error> {
-        match s.0 {
-            SmallIntType::Inline(i) => {
-                u128::try_from(i).map_err(|_| SmallIntError::ConversionError)
-            }
-            SmallIntType::Heap((r, s)) => {
-                let mut ret: u128 = 0;
-                let mut bits = 0;
-                let size = usize::try_from(s.abs()).unwrap();
-                let slice = unsafe { core::slice::from_raw_parts(r, size) };
-                for i in slice {
-                    if bits >= 128 {
-                        return Err(SmallIntError::ConversionError);
-                    }
-                    ret |= u128::from(*i) << bits;
-                    bits += 32;
-                }
-
-                Ok(ret)
-            }
-        }
-    }
-}
-
-impl From<SmallUint> for SmallInt {
-    fn from(s: SmallUint) -> Self {
-        match s.0 {
-            SmallUintType::Inline(i) => SmallInt::from(i),
-            SmallUintType::Heap((r, s)) => {
-                SmallInt(SmallIntType::Heap((r, isize::try_from(s).unwrap())))
-            }
-        }
-    }
-}
-
-impl TryFrom<SmallInt> for SmallUint {
-    type Error = SmallIntError;
-
-    fn try_from(value: SmallInt) -> Result<Self, Self::Error> {
-        match value.0 {
-            SmallIntType::Inline(i) => Self::try_from(i),
-            SmallIntType::Heap((r, s)) => {
-                let size = usize::try_from(s).map_err(|_| SmallIntError::ConversionError)?;
-                if size > 4 {
-                    Ok(Self(SmallUintType::Heap((r, size))))
-                } else {
-                    Ok(Self(SmallUintType::Inline(u128::try_from(value)?)))
-                }
-            }
-        }
-    }
-}
-
-#[cfg(feature = "num-bigint")]
-impl From<&BigInt> for SmallInt {
-    fn from(b: &BigInt) -> Self {
-        match b.try_into() {
-            Ok(i) => Self(SmallIntType::Inline(i)),
-            Err(_) => {
-                let (sign, vec) = b.to_u32_digits();
-                let mut slice = ManuallyDrop::new(vec.into_boxed_slice());
-                let size = match sign {
-                    Sign::Minus => -isize::try_from(slice.len()).unwrap(),
-                    Sign::NoSign => panic!(
-                        "Shouldn't happen; BigInts which store zero should convert to inline."
-                    ),
-                    Sign::Plus => isize::try_from(slice.len()).unwrap(),
-                };
-                Self(SmallIntType::Heap((slice.as_mut_ptr(), size)))
-            }
-        }
-    }
-}
-
-#[cfg(feature = "num-bigint")]
-impl From<&SmallInt> for BigInt {
-    fn from(s: &SmallInt) -> Self {
-        match s.0 {
-            SmallIntType::Inline(i) => Self::from(i),
-            SmallIntType::Heap((r, s)) => {
-                let size = usize::try_from(s.abs()).unwrap();
-                let sign = s.signum();
-                let slice = unsafe { core::slice::from_raw_parts(r, size) };
-                let bs = match sign {
-                    0 => Sign::NoSign,
-                    -1 => Sign::Minus,
-                    1 => Sign::Plus,
-                    _ => panic!("This shouldn't happen; There are only 3 signums."),
-                };
-
-                BigInt::new(bs, slice.to_vec())
-            }
-        }
-    }
-}
-
-#[cfg(feature = "num-bigint")]
-impl From<&BigUint> for SmallUint {
-    fn from(b: &BigUint) -> Self {
-        match b.try_into() {
-            Ok(i) => Self(SmallUintType::Inline(i)),
-            Err(_) => {
-                let vec = b.to_u32_digits();
-                let mut slice = ManuallyDrop::new(vec.into_boxed_slice());
-                let size = slice.len();
-                Self(SmallUintType::Heap((slice.as_mut_ptr(), size)))
-            }
-        }
-    }
-}
-
-#[cfg(feature = "num-bigint")]
-impl From<&SmallUint> for BigUint {
-    fn from(s: &SmallUint) -> Self {
-        match s.0 {
-            SmallUintType::Inline(i) => Self::from(i),
-            SmallUintType::Heap((r, s)) => {
-                let slice = unsafe { core::slice::from_raw_parts(r, s) };
-
-                BigUint::new(slice.to_vec())
-            }
-        }
-    }
-}
-
-#[cfg(test)]
-mod conversion_tests {
-
-    use crate::SmallInt;
-    use crate::SmallUint;
-
-    #[cfg(feature = "num-bigint")]
-    use num_bigint::{BigInt, Sign, BigUint, };
-
-    macro_rules! conversion_tests {
-        ($t:ty, $i:ident) => {
-            #[test]
-            fn $i() {
-                let i = <$t>::MAX;
-                let s = SmallInt::from(i);
-                assert_eq!(<$t>::try_from(s).unwrap(), i);
-
-                let i = <$t>::MIN;
-                let s = SmallInt::from(i);
-                assert_eq!(<$t>::try_from(s).unwrap(), i);
-            }
-        };
-    }
-
-    conversion_tests!(u8, test_u8);
-    conversion_tests!(i8, test_i8);
-    conversion_tests!(u16, test_u16);
-    conversion_tests!(i16, test_i16);
-    conversion_tests!(u32, test_u32);
-    conversion_tests!(i32, test_i32);
-    conversion_tests!(u64, test_u64);
-    conversion_tests!(i64, test_i64);
-    conversion_tests!(u128, test_u128);
-    conversion_tests!(i128, test_i128);
-
-    #[test]
-    #[cfg(feature = "num-bigint")]
-    fn test_op_add_u_u() {
-        let i = SmallUint::from(u128::MAX);
-        let k = SmallUint::from(&BigUint::new(vec![5, 4, 9, 3, 2, 1, 5]));
-        let q = i + k;
-        println!("{:?}", BigUint::from(&q));
-        println!("{:?}", BigUint::new(vec![5, 4, 9, 3, 2, 1, 5]) + u128::MAX);
-
-    }
-
-    #[test]
-    #[cfg(feature = "num-bigint")]
-    fn test_bigint() {
-        let i = BigInt::new(Sign::Plus, vec![5, 4, 8, 3, 2, 9, 3]);
-        let s = SmallInt::from(&i);
-        assert_eq!(
-            BigInt::from(&s).to_u32_digits(),
-            (Sign::Plus, vec![5, 4, 8, 3, 2, 9, 3])
-        );
-    }
-}

src/ops.rs

@@ -0,0 +1,243 @@
+use crate::SmallUint;
+use crate::smallint::SmallUintType;
+use core::ops::Add;
+use core::mem::ManuallyDrop;
+
+macro_rules! basic_op {
+    ($imp:ident, $typ:ty, $fun:ident) => {
+
+        impl<'a, 'b> $imp<&'a $typ> for &'b $typ {
+
+            type Output = $typ;
+
+            fn $fun(self, rhs: &$typ) -> Self::Output {
+                $fun(self, rhs)
+            }
+
+        }
+
+        impl<'a> $imp<$typ> for &'a $typ {
+
+            type Output = $typ;
+
+            fn $fun(self, rhs: $typ) -> Self::Output {
+                self.$fun(&rhs)
+            }
+
+        }
+
+        impl<'a> $imp<&'a $typ> for $typ {
+
+            type Output = $typ;
+
+            fn $fun(self, rhs: &$typ) -> Self::Output {
+                (&self).$fun(rhs)
+            }
+
+        }
+
+
+        impl $imp<$typ> for $typ {
+
+            type Output = $typ;
+
+            fn $fun(self, rhs: $typ) -> Self::Output {
+                (&self).$fun(&rhs)
+            }
+
+        }
+    }
+}
+
+
+fn add_two_slices(slice1: &[u32], slice2: &[u32]) -> Vec<u32> {
+
+    let s = slice1.len();
+    let j = slice2.len();
+
+    let larger = std::cmp::max(s, j);
+    let mut res = Vec::with_capacity(larger + 1);
+    let mut carry = false;
+
+    for t in 0..larger {
+
+        let value1 = if t < s {
+            slice1[t]
+        } else {
+            0
+        };
+
+        let value2 = if t < j {
+            slice2[t]
+        } else {
+            0
+        };
+
+        let (val, overflow) = value1.overflowing_add(value2);
+        let (cval, coverflow) = val.overflowing_add(carry as u32);
+        res.push(cval);
+        carry = overflow | coverflow;
+
+    }
+
+    if carry {
+        res.push(1);
+    }
+    while res[res.len() - 1] == 0 {
+        res.pop();
+    }
+    res
+}
+
+fn add(a: &SmallUint, b: &SmallUint) -> SmallUint {
+
+    match (&a.0, &b.0) {
+        (&SmallUintType::Inline(i), &SmallUintType::Inline(j)) => {
+            match i.overflowing_add(j) {
+                (t, false) => SmallUint(SmallUintType::Inline(t)),
+                (t, true) => {
+                    let mut res = [0, 0, 0, 0, 1];
+
+                    let mut v = t;
+                    #[allow(clippy::needless_range_loop)]
+                    for r in 0..4 {
+                        res[r] = v as u32;
+
+                        v >>= 32;
+                    }
+
+                    let mut slice = ManuallyDrop::new(<Box<[u32]>>::from(res));
+
+                    SmallUint(SmallUintType::Heap((slice.as_mut_ptr(), 5)))
+
+                }
+            }
+        },
+        (&SmallUintType::Heap((r, s)), &SmallUintType::Inline(i)) | (&SmallUintType::Inline(i), &SmallUintType::Heap((r, s))) => {
+            let slice1 = unsafe { core::slice::from_raw_parts(r, s) };
+
+            let mut res = [0, 0, 0, 0];
+
+            let mut v = i;
+            #[allow(clippy::needless_range_loop)]
+            for r in 0..4 {
+                res[r] = v as u32;
+
+                v >>= 32;
+            }
+
+            let result = add_two_slices(slice1, &res[..]);
+            let size = result.len();
+
+            let mut slice = ManuallyDrop::new(result.into_boxed_slice());
+
+            SmallUint(SmallUintType::Heap((slice.as_mut_ptr(), size)))
+
+
+        },
+        (&SmallUintType::Heap((r, s)), &SmallUintType::Heap((i, j))) => {
+
+            let slice1 = unsafe { core::slice::from_raw_parts(r, s) };
+            let slice2 = unsafe { core::slice::from_raw_parts(i, j) };
+
+            let res = add_two_slices(slice1, slice2);
+            let size = res.len();
+
+            let mut slice = ManuallyDrop::new(res.into_boxed_slice());
+
+            SmallUint(SmallUintType::Heap((slice.as_mut_ptr(), size)))
+
+        }
+    }
+}
+
+basic_op!(Add, SmallUint, add);
+
+// Taken from https://github.com/rust-lang/rust/issues/85532#issuecomment-916309635. Credit to
+// AaronKutch.
+const fn carrying_mul_u128(lhs: u128, rhs: u128, carry: u128) -> (u128, u128) {
+    //                       [rhs_hi]  [rhs_lo]
+    //                       [lhs_hi]  [lhs_lo]
+    //                     X___________________
+    //                       [------tmp0------]
+    //             [------tmp1------]
+    //             [------tmp2------]
+    //     [------tmp3------]
+    //                       [-------add------]
+    // +_______________________________________
+    //                       [------sum0------]
+    //     [------sum1------]
+
+    let lhs_lo = lhs as u64;
+    let rhs_lo = rhs as u64;
+    let lhs_hi = (lhs.wrapping_shr(64)) as u64;
+    let rhs_hi = (rhs.wrapping_shr(64)) as u64;
+    let tmp0 = (lhs_lo as u128).wrapping_mul(rhs_lo as u128);
+    let tmp1 = (lhs_lo as u128).wrapping_mul(rhs_hi as u128);
+    let tmp2 = (lhs_hi as u128).wrapping_mul(rhs_lo as u128);
+    let tmp3 = (lhs_hi as u128).wrapping_mul(rhs_hi as u128);
+    // tmp1 and tmp2 straddle the boundary. We have to handle three carries
+    let (sum0, carry0) = tmp0.overflowing_add(tmp1.wrapping_shl(64));
+    let (sum0, carry1) = sum0.overflowing_add(tmp2.wrapping_shl(64));
+    let (sum0, carry2) = sum0.overflowing_add(carry);
+    let sum1 = tmp3
+        .wrapping_add(tmp1.wrapping_shr(64))
+        .wrapping_add(tmp2.wrapping_shr(64))
+        .wrapping_add(carry0 as u128)
+        .wrapping_add(carry1 as u128)
+        .wrapping_add(carry2 as u128);
+    (sum0, sum1)
+}
+
+// fn mul_two_slices(slice1: &[u32], slice2: &[u32]) -> Vec<u32> {
+// 
+//     let l1 = slice1.len();
+//     let l2 = slice2.len();
+// 
+// 
+// }
+// 
+// 
+// fn mul(a: &SmallUint, b: &SmallUint) -> SmallUint {
+//     match (&a.0, &b.0) {
+//         (&SmallUintType::Inline(i), &SmallUintType::Inline(j)) => {
+//             match carrying_mul_u128(i, j, 0) {
+//                 (t, 0) => SmallUint(SmallUintType::Inline(t)),
+//                 (t, o) => {
+//                     let mut res = Vec::with_capacity(8);
+// 
+//                     let mut v = t;
+//                     #[allow(clippy::needless_range_loop)]
+//                     for _ in 0..4 {
+//                         res.push(v as u32);
+// 
+//                         v >>= 32;
+//                     }
+// 
+//                     let mut v = o;
+//                     for _ in 4..8 {
+//                         res.push(v as u32);
+// 
+//                         v >>= 32;
+//                     }
+// 
+//                     while res[res.len() - 1] == 0 {
+//                         res.pop();
+//                     }
+// 
+//                     let size = res.len();
+// 
+//                     let mut slice = ManuallyDrop::new(res.into_boxed_slice());
+// 
+//                     SmallUint(SmallUintType::Heap((slice.as_mut_ptr(), size)))
+// 
+//                 }
+//             }
+//         },
+//         (&SmallUintType::Heap((r, s)), &SmallUintType::Inline(i)) | (&SmallUintType::Inline(i), &SmallUintType::Heap((r, s))) => {
+// 
+//         }
+//     }
+// }
+// 
+// 

src/pretty.rs

@@ -0,0 +1,22 @@
+use crate::SmallInt;
+use crate::SmallUint;
+
+
+#[cfg(feature= "num-bigint")]
+use num_bigint::{BigInt, BigUint};
+
+
+#[cfg(feature = "num-bigint")]
+impl core::fmt::Debug for SmallInt {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", BigInt::from(self))
+    }
+}
+
+#[cfg(feature = "num-bigint")]
+impl core::fmt::Debug for SmallUint {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", BigUint::from(self))
+    }
+}
+

src/smallint.rs

@@ -0,0 +1,43 @@
+
+/// An integer-like type that will store small integers up to `i128` inline. Larger integers are
+/// represented as a slice to a sequence of base 2<sup>32</sup> digits represented as a `*mut u32`.
+#[derive(Clone, PartialEq, Eq)]
+pub struct SmallInt(pub(crate) SmallIntType);
+
+/// An integer-like type that will store small integers up to `u128` inline. Larger integers are
+/// represented as a slice to a sequence of base 2<sup>32</sup> digits represented as a `*mut u32`.
+#[derive(Clone, PartialEq, Eq)]
+pub struct SmallUint(pub(crate) SmallUintType);
+
+#[derive(Clone, PartialEq, Eq)]
+pub enum SmallIntType {
+    Inline(i128),
+    Heap((*mut u32, isize)),
+}
+
+#[derive(Clone, PartialEq, Eq)]
+pub enum SmallUintType {
+    Inline(u128),
+    Heap((*mut u32, usize)),
+}
+
+
+impl Drop for SmallInt {
+    fn drop(&mut self) {
+        if let Self(SmallIntType::Heap((r, s))) = self {
+            let size = usize::try_from(s.abs()).unwrap();
+            let slice = unsafe { core::slice::from_raw_parts_mut(*r, size) };
+            unsafe { std::mem::drop(Box::from_raw(slice)) }
+        }
+    }
+}
+
+impl Drop for SmallUint {
+    fn drop(&mut self) {
+        if let Self(SmallUintType::Heap((r, s))) = self {
+            let slice = unsafe { core::slice::from_raw_parts_mut(*r, *s) };
+            unsafe { std::mem::drop(Box::from_raw(slice)) }
+        }
+    }
+}
+

src/tests.rs

@@ -0,0 +1,63 @@
+#![cfg(test)]
+
+use crate::SmallInt;
+use crate::SmallUint;
+
+#[cfg(feature = "num-bigint")]
+use num_bigint::{BigInt, Sign, BigUint};
+
+macro_rules! conversion_tests {
+    ($t:ty, $i:ident) => {
+        #[test]
+        fn $i() {
+            let i = <$t>::MAX;
+            let s = SmallInt::from(i);
+            assert_eq!(<$t>::try_from(s).unwrap(), i);
+
+            let i = <$t>::MIN;
+            let s = SmallInt::from(i);
+            assert_eq!(<$t>::try_from(s).unwrap(), i);
+        }
+    };
+}
+
+conversion_tests!(u8, test_u8);
+conversion_tests!(i8, test_i8);
+conversion_tests!(u16, test_u16);
+conversion_tests!(i16, test_i16);
+conversion_tests!(u32, test_u32);
+conversion_tests!(i32, test_i32);
+conversion_tests!(u64, test_u64);
+conversion_tests!(i64, test_i64);
+conversion_tests!(u128, test_u128);
+conversion_tests!(i128, test_i128);
+
+#[test]
+#[cfg(feature = "num-bigint")]
+fn test_op_add_u_u() {
+    let i = SmallUint::from(u128::MAX);
+    let k = SmallUint::from(u128::MAX);
+    let q = i + k;
+    assert_eq!(BigUint::from(&q), BigUint::from(u128::MAX) + u128::MAX);
+
+    let i = SmallUint::from(u128::MAX);
+    let k = SmallUint::from(&BigUint::new(vec![5, 4, 9, 3, 1, 81]));
+    let q = i + k;
+    assert_eq!(BigUint::from(&q), BigUint::new(vec![5, 4, 9, 3, 1, 81]) + u128::MAX);
+
+    let i = SmallUint::from(&BigUint::new(vec![3, 9, 8]));
+    let k = SmallUint::from(&BigUint::new(vec![5, 4, 9, 3, 1, 81]));
+    let q = i + k;
+    assert_eq!(BigUint::from(&q), BigUint::new(vec![3, 9, 8]) + BigUint::new(vec![5, 4, 9, 3, 1, 81]));
+}
+
+#[test]
+#[cfg(feature = "num-bigint")]
+fn test_bigint() {
+    let i = BigInt::new(Sign::Plus, vec![5, 4, 8, 3, 2, 9, 3]);
+    let s = SmallInt::from(&i);
+    assert_eq!(
+        BigInt::from(&s).to_u32_digits(),
+        (Sign::Plus, vec![5, 4, 8, 3, 2, 9, 3])
+    );
+}