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diff --git a/bzipper_macros/src/discriminant/mod.rs b/bzipper_macros/src/discriminant/mod.rs
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+++ b/bzipper_macros/src/discriminant/mod.rs
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+// Copyright 2024 Gabriel Bjørnager Jensen.
+//
+// This file is part of bzipper.
+//
+// bzipper is free software: you can redistribute
+// it and/or modify it under the terms of the GNU
+// Lesser General Public License as published by
+// the Free Software Foundation, either version 3
+// of the License, or (at your option) any later
+// version.
+//
+// bzipper is distributed in the hope that it will
+// be useful, but WITHOUT ANY WARRANTY; without
+// even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Less-
+// er General Public License along with bzipper. If
+// not, see <https://www.gnu.org/licenses/>.
+
+use proc_macro2::TokenStream;
+use quote::ToTokens;
+
+/// An enumeration discriminant.
+#[derive(Clone, Copy)]
+#[repr(transparent)]
+pub struct Discriminant(u32);
+
+impl Discriminant {
+ /// Constructs a new discriminant.
+ #[inline(always)]
+ #[must_use]
+ pub const fn new(value: u32) -> Self { Self(value) }
+
+ /// Retrieves the raw discriminant value.
+ #[inline(always)]
+ #[must_use]
+ pub const fn get(self) -> u32 { self.0 }
+
+ /// Unwraps the given value as a discriminant.
+ ///
+ /// # Panics
+ ///
+ /// If the given value cannot be represented as an `u32`, this function will panic.
+ #[inline(always)]
+ #[must_use]
+ pub fn unwrap_from<T: TryInto<Self>>(value: T) -> Self {
+ value
+ .try_into()
+ .unwrap_or_else(|_| panic!("enumeration discriminants must be representable in `u32`"))
+ }
+
+ /// Unsafely unwraps the given value as a discriminant.
+ ///
+ /// This function assumes that this conversion is infallible for the given value.
+ /// If this is a false guarantee, the [`unwrap_from`](Self::unwrap_from) function should be used instead.
+ ///
+ /// # Safety
+ ///
+ /// Behaviour is undefined if the given value cannot be represented as an object of `u32`.
+ #[inline(always)]
+ #[must_use]
+ pub unsafe fn unwrap_from_unchecked<T: TryInto<Self>>(value: T) -> Self {
+ value
+ .try_into()
+ .unwrap_unchecked()
+ }
+}
+
+impl ToTokens for Discriminant {
+ #[inline(always)]
+ fn to_tokens(&self, tokens: &mut TokenStream) { self.0.to_tokens(tokens) }
+}
+
+impl From<u32> for Discriminant {
+ #[inline(always)]
+ fn from(value: u32) -> Self { Self(value) }
+}
+
+impl TryFrom<usize> for Discriminant {
+ type Error = <u32 as TryFrom<usize>>::Error;
+
+ #[inline(always)]
+ fn try_from(value: usize) -> Result<Self, Self::Error> { value.try_into().map(Self) }
+}
+
+impl From<Discriminant> for u32 {
+ #[inline(always)]
+ fn from(value: Discriminant) -> Self { value.0 }
+}
+
+impl TryFrom<Discriminant> for usize {
+ type Error = <Self as TryFrom<u32>>::Error;
+
+ #[inline(always)]
+ fn try_from(value: Discriminant) -> Result<Self, Self::Error> { value.0.try_into() }
+}