move data::convert types and traits to num and rename

- rename  `Casting` to `Primiting`.
- rename `CastPrimitives` to `PrimitiveCast`.
- rename `FromPrimitives` to `PrimitiveJoin`.
- rename `IntoPrimitives` to `PrimitiveSplit`.

src/data/mod.rs

@@ -23,12 +23,11 @@ mod error;
 pub mod bit;
 pub mod cmp;
 pub mod collections;
-pub mod convert;
 pub mod hash;
 
 #[allow(unused)]
 #[cfg(not(feature = "data"))]
-pub use {bit::*, cmp::*, collections::*, convert::*, error::*, hash::*};
+pub use {bit::*, cmp::*, collections::*, error::*, hash::*};
 
 /* feature-gated */
 
@@ -60,15 +59,11 @@ pub use error::*;
 pub use dst::*;
 #[doc(no_inline)]
 #[cfg(feature = "data")]
-pub use {
-    any::all::*, bit::all::*, cmp::all::*, collections::all::*, convert::all::*, hash::all::*,
-};
+pub use {any::all::*, bit::all::*, cmp::all::*, collections::all::*, hash::all::*};
 
 pub(crate) mod all {
     #[doc(inline)]
-    pub use super::{
-        bit::all::*, cmp::all::*, collections::all::*, convert::all::*, error::*, hash::all::*,
-    };
+    pub use super::{bit::all::*, cmp::all::*, collections::all::*, error::*, hash::all::*};
 
     #[doc(inline)]
     #[cfg(feature = "data")]

src/num/int/wrapper/impl_combinatorics.rs

@@ -10,10 +10,10 @@
 //   - permute
 //   - permute_rep
 
-use super::Int;
-use crate::code::{cfor, iif, paste};
-use crate::data::Casting;
-use crate::num::{NumErrors as E, NumResult as Result};
+use crate::{
+    code::{cfor, iif, paste},
+    num::{Int, NumErrors as E, NumResult as Result, Primiting},
+};
 use E::{MismatchedSizes, NonNegativeRequired, Overflow};
 
 // $t:   the input/output type
@@ -195,7 +195,7 @@ macro_rules! impl_combinatorics {
             pub const fn permute_rep(self, r: $t) -> Result<Int<$t>> {
                 let n = self.0;
                 iif![n < 0 || r < 0; return Err(NonNegativeRequired)];
-                let r_u32 = if let Ok(res) = Casting(r).checked_cast_to_u32() {
+                let r_u32 = if let Ok(res) = Primiting(r).checked_cast_to_u32() {
                     res
                 } else {
                     return Err(Overflow(None));
@@ -455,7 +455,7 @@ macro_rules! impl_combinatorics {
             #[inline]
             pub const fn permute_rep(self, r: $t) -> Result<Int<$t>> {
                 let n = self.0;
-                let r_u32 = if let Ok(res) = Casting(r).checked_cast_to_u32() {
+                let r_u32 = if let Ok(res) = Primiting(r).checked_cast_to_u32() {
                     res
                 } else {
                     return Err(Overflow(None));

src/num/int/wrapper/impl_core.rs

@@ -15,8 +15,10 @@
 //   - gcd_ext_euc
 
 use super::Int;
-use crate::code::{iif, paste};
-use crate::num::{isize_up, usize_up, NumErrors, NumResult as Result};
+use crate::{
+    code::{iif, paste},
+    num::{isize_up, usize_up, Casting, NumErrors, NumResult as Result},
+};
 use NumErrors::Overflow;
 
 // $t:   the input/output type

src/num/mod.rs

@@ -13,6 +13,7 @@ mod _private;
 mod alias;
 mod error;
 mod float;
+mod primitive;
 mod sign;
 
 pub mod niche;
@@ -22,7 +23,7 @@ pub mod ops;
 pub(crate) use _private::*;
 #[allow(unused)]
 #[cfg(not(feature = "num"))]
-pub use {alias::*, error::*, float::*, niche::*, ops::*, sign::*};
+pub use {alias::*, error::*, float::*, niche::*, ops::*, primitive::*, sign::*};
 
 /* feature-gated */
 
@@ -37,7 +38,7 @@ mod r#trait;
 
 // re-export private sub-modules
 #[cfg(feature = "num")]
-pub use {alias::*, error::*, float::*, frac::*, int::*, no::*, r#trait::*, sign::*};
+pub use {alias::*, error::*, float::*, frac::*, int::*, no::*, primitive::*, r#trait::*, sign::*};
 
 // re-export public sub-modules
 #[doc(no_inline)]
@@ -46,7 +47,9 @@ pub use {niche::all::*, ops::all::*};
 
 pub(crate) mod all {
     #[doc(inline)]
-    pub use super::{alias::*, error::*, float::*, niche::all::*, ops::all::*, sign::*};
+    pub use super::{
+        alias::*, error::*, float::*, niche::all::*, ops::all::*, primitive::*, sign::*,
+    };
 
     #[doc(inline)]
     #[cfg(feature = "num")]

src/data/convert/cast/casts.rs → src/num/primitive/casts.rs

@@ -7,21 +7,23 @@
 // - trait and wrapper implementation
 // - functions definitions
 
-use super::Casting;
 use crate::{
     code::{iif, paste},
-    data::{DataErrors as E, DataResult as Result},
+    num::{NumErrors, NumResult as Result, Primiting, Sign},
+};
+use {
+    NumErrors::Overflow,
+    Sign::{Negative, Positive},
 };
-#[cfg(doc)]
-use E::{Overflow, Underflow};
 
 /// Offers methods for casting between primitives.
 ///
+/// See also the [`Primiting`] type for the equivalent *const* methods.
 /// # Errors
-/// Checked methods will return [`Overflow`] or [`Underflow`] if `self` value can't fit
-/// in the returned type.
+/// Checked methods will return [`Overflow`]
+/// if the original value can't fit in the returned type.
 #[cfg_attr(feature = "nightly", doc(cfg(feature = "data")))]
-pub trait CastPrimitives {
+pub trait PrimitiveCast {
     /// Casts `self` to `u8` with range check.
     fn checked_cast_to_u8(self) -> Result<u8>;
     /// Casts `self` to `u16` with range check.
@@ -84,11 +86,11 @@ pub trait CastPrimitives {
     fn saturating_cast_to_isize(self) -> isize;
 }
 
-// Implements the public casting methods for the trait and Casting wrapper
+// Implements the public casting methods for the trait and Primiting wrapper
 macro_rules! impl_cast_methods {
     ($($t:ty),+) => { $( impl_cast_methods![@$t]; )+ };
     (@$t:ty) => { paste! {
-        impl CastPrimitives for $t {
+        impl PrimitiveCast for $t {
             #[inline(always)]
             fn checked_cast_to_u8(self) -> Result<u8> { [<checked_cast_ $t _to_u8>](self) }
             #[inline(always)]
@@ -142,9 +144,8 @@ macro_rules! impl_cast_methods {
         /// Checked casts and saturating casts.
         ///
         /// # Errors
-        /// Checked methods will return [`Overflow`] or [`Underflow`] if `self` value can't fit
-        /// in the returned type.
-        impl Casting<$t> {
+        /// Checked methods will return [`Overflow`] if `self` can't fit in the returned type.
+        impl Primiting<$t> {
             #[doc = "Casts from `" $t "` to `u8` with range check."]
             #[inline(always)]
             pub const fn checked_cast_to_u8(self) -> Result<u8> {
@@ -432,9 +433,9 @@ macro_rules! impl_cast_fns {
         #[inline]
         const fn [<checked_cast_ $f _to_ $t>](p: $f) -> Result<$t> {
             if p < <$t>::MIN as $f {
-                Err(E::Underflow)
+                Err(Overflow(Some(Negative)))
             } else if p > $t::MAX as $f {
-                Err(E::Overflow)
+                Err(Overflow(Some(Positive)))
             } else {
                 Ok(p as $t)
             }
@@ -454,7 +455,7 @@ macro_rules! impl_cast_fns {
     (@can_overflow $f:ty:$t:ty) => { paste! {
         #[inline]
         const fn [<checked_cast_ $f _to_ $t>](p: $f) -> Result<$t> {
-            iif![p > <$t>::MAX as $f; Err(E::Overflow); Ok(p as $t)]
+            iif![p > <$t>::MAX as $f; Err(Overflow(Some(Positive))); Ok(p as $t)]
         }
         #[must_use] #[inline]
         const fn [<saturating_cast_ $f _to_ $t>](p: $f) -> $t {
@@ -465,7 +466,7 @@ macro_rules! impl_cast_fns {
     (@can_underflow $f:ty:$t:ty) => { paste! {
         #[inline]
         const fn [<checked_cast_ $f _to_ $t>](p: $f) -> Result<$t> {
-            iif![p < 0; Err(E::Underflow); Ok(p as $t)]
+            iif![p < 0; Err(Overflow(Some(Negative))); Ok(p as $t)]
         }
         #[must_use] #[inline]
         const fn [<saturating_cast_ $f _to_ $t>](p: $f) -> $t {