feat: meta update; this is 0.2.0!

.gitignore

@@ -1 +1,2 @@
 /target
+Cargo.lock

Cargo.lock

@@ -1,5 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-[[package]]
-name = "nslice"
-version = "0.1.0"

Cargo.toml

@@ -1,10 +1,11 @@
 [package]
 name = "nslice"
-version = "0.1.0"
+version = "0.2.0"
 authors = ["Leonora Tindall <nora@nora.codes>"]
-edition = "2018"
+edition = "2021"
 description = "Structures for interpreting slices of variable length as arrays"
 license = "MIT"
 keywords = ["memory", "slice", "array"]
 categories = ["data-structures"]
 repository = "https://git.nora.codes/nora/nslice"
+readme = "README.md"

README.md

@@ -0,0 +1,25 @@
+# nslice
+
+Structures for interpreting slices of variable length as arrays.
+
+`nslice` provides `MinSlice` and `ExactSlice` for representing slices known to have
+either exactly or at least some compile-time-known number of values.
+
+This is useful when dealing with a slice whose length you expect to be exactly
+or at least some particular length;
+rather than making runtime checks on each access,
+you can check the length once and access values freely with no copying. 
+
+```rust
+# use nslice::MinSlice;
+
+let slice = &[1, 2, 3, 4, 5, 6];
+let minslice: &MinSlice<_, 3> = MinSlice::from_slice(slice).unwrap();
+assert_eq!(minslice.tail.len(), 3);
+assert_eq!(minslice.head[0], 1);
+assert_eq!(minslice.tail[2], 6);
+``` 
+
+## License
+
+This project is licensed MIT.

src/lib.rs

@@ -1,15 +1,4 @@
-//! Structures for interpreting slices of variable length as arrays.
-//!
-//! `nslice` provides `MinSlice` and `ExactSlice` for representing slices known to have
-//! either exactly or at least some compile-time-known number of values.
-//! ```
-//! use nslice::MinSlice;
-//! let slice = &[1, 2, 3, 4, 5, 6];
-//! let minslice: &MinSlice<_, 3> = MinSlice::from_slice(slice).unwrap();
-//! assert_eq!(minslice.tail.len(), 3);
-//! assert_eq!(minslice.head[0], 1);
-//! assert_eq!(minslice.tail[2], 6);
-//! ```
+#![doc=include_str!("../README.md")]
 use std::slice;
 
 /// A reference to a region of memory which is known to contain `N` or more elements
@@ -19,6 +8,16 @@ use std::slice;
 /// `MinSlice` is merely a way of reinterpreting an existing slice
 /// (`&[T]` or `&mut [T]`), and it is exactly the same size as a slice:
 /// one pointer and one `usize`.
+/// 
+/// # Example
+/// 
+/// ```
+/// # use nslice::MinSlice;
+/// let slice: &[u8] = b"Hello, world";
+/// let minslice = MinSlice::<u8, 12>::from_slice(slice).unwrap();
+/// let value: u8 = minslice.head[6];
+/// assert_eq!(value, b' ')
+/// ```
 pub struct MinSlice<T, const N: usize> {
     /// The bounded region of memory. Exactly `N` `T`s.
     pub head: [T; N],
@@ -57,6 +56,56 @@ impl<T, const N: usize> MinSlice<T, N> {
             None
         }
     }
+}
+
+impl<T, const N: usize> MinSlice<T, N> {
+    /// Returns a slice over the memory referred to by the `MinSlice`.
+    /// Its length is guaranteed to be no less than `N`.
+    pub fn as_slice(&self) -> &[T] {
+        unsafe { slice::from_raw_parts(self.head.as_ptr(), N + self.tail.len()) }
+    }
+
+    /// Returns a mutable slice over the memory referred to by the `MinSlice`.
+    /// Its length is guaranteed to be no less than `N`.
+    pub fn as_mut_slice(&mut self) -> &mut [T] {
+        unsafe { slice::from_raw_parts_mut(self.head.as_mut_ptr(), N + self.tail.len()) }
+    }
+
+    /// Resize the `MinSlice`, returning a new `Some(&MinSlice<T, M>)`
+    /// if there are at least `M` `T`s in `self`. 
+    pub fn resize<const M: usize>(&self) -> Option<&MinSlice<T, M>> {
+        MinSlice::<T, M>::from_slice(self.as_slice())
+    }
+
+    /// Resize the `MinSlice`, returning a new `Some(&mut MinSlice<T, M>)`
+    /// if there are at least `M` `T`s in `self`. 
+    pub fn resize_mut<const M: usize>(&mut self) -> Option<&mut MinSlice<T, M>> {
+        MinSlice::<T, M>::from_mut(self.as_mut_slice())
+    }
+
+    /// Get a reference to a value from the `MinSlice` by index.
+    /// 
+    /// Return `Some(&T)` for the `T` at index `i` if `i < (N + self.tail.len)`,
+    /// or `None` otherwise.
+    pub fn get(&self, i: usize) -> Option<&T> {
+        if i < N {
+            Some(&self.head[i])
+        } else {
+            self.tail.get(i)
+        }
+    }
+
+    /// Get a mutable reference to a value from the `MinSlice` by index.
+    /// 
+    /// Return `Some(&mut T)` for the `T` at index `i` if `i < (N + self.tail.len)`,
+    /// or `None` otherwise.
+    pub fn get_mut(&mut self, i: usize) -> Option<&mut T> {
+        if i < N {
+            Some(&mut self.head[i])
+        } else {
+            self.tail.get_mut(i)
+        }
+    } 
 
     /// Produce a `&MinSlice` from a slice of `T`s without checking its length.
     ///
@@ -112,14 +161,26 @@ impl<T, const N: usize> ExactSlice<T, N> {
         }
     }
 
+    /// Returns a slice over the memory referred to by the `ExactSlice`.
+    /// Its length is guaranteed to be exactly `N`.
+    pub fn as_slice(&self) -> &[T] {
+        unsafe { slice::from_raw_parts(self.head.as_ptr(), N) }
+    }
+
+    /// Returns a mutable slice over the memory referred to by the `ExactSlice`.
+    /// Its length is guaranteed to be exactly `N`.
+    pub fn as_mut_slice(&mut self) -> &mut [T] {
+        unsafe { slice::from_raw_parts_mut(self.head.as_mut_ptr(), N) }
+    }
+
     /// Produce a `&MinSlice` from this `&ExactSlice`. Its `tail` will be empty.
-    pub fn as_min_slice(&self) -> Option<&MinSlice<T, N>> {
-        MinSlice::from_slice(&self.head[..])
+    pub fn as_min_slice(&self) -> &MinSlice<T, N> {
+        unsafe { MinSlice::from_slice_unchecked(&self.head[..]) }
     }
 
     /// Produce a `&mut MinSlice` from this `&min ExactSlice`. Its `tail` will be empty.
-    pub fn as_mut_min_slice(&mut self) -> Option<&mut MinSlice<T, N>> {
-        MinSlice::from_mut(&mut self.head[..])
+    pub fn as_mut_min_slice(&mut self) -> &mut MinSlice<T, N> {
+        unsafe { MinSlice::from_mut_unchecked(&mut self.head[..]) }
     }
 
     /// Produce an `&ExactSlice` from a slice of `T`s without checking its length.
@@ -143,6 +204,30 @@ impl<T, const N: usize> ExactSlice<T, N> {
     }
 }
 
+impl<'a, T, const N: usize> Into<&'a MinSlice<T, N>> for &'a ExactSlice<T, N> {
+    fn into(self) -> &'a MinSlice<T, N> {
+        self.as_min_slice()
+    }
+}
+
+impl<'a, T, const N: usize> Into<&'a mut MinSlice<T, N>> for &'a mut ExactSlice<T, N> {
+    fn into(self) -> &'a mut MinSlice<T, N> {
+        self.as_mut_min_slice()
+    }
+}
+
+impl<'a, T, const N: usize> Into<&'a ExactSlice<T, N>> for &'a MinSlice<T, N> {
+    fn into(self) -> &'a ExactSlice<T, N> {
+        unsafe { ExactSlice::from_slice_unchecked(&self.head[..]) }
+    }
+}
+
+impl<'a, T, const N: usize> Into<&'a mut ExactSlice<T, N>> for &'a mut MinSlice<T, N> {
+    fn into(self) -> &'a mut ExactSlice<T, N> {
+        unsafe { ExactSlice::from_mut_unchecked(&mut self.head[..]) }
+    }
+}
+
 #[test]
 fn basic_min_success() {
     let slice = &[1, 2, 3, 4, 5, 6];