#![cfg_attr(feature = "external_doc", feature(external_doc))]
#![cfg_attr(feature = "external_doc", doc(include = "../README.md"))]
#![cfg_attr(
not(feature = "external_doc"),
doc = "See https://docs.rs/num_enum for more info about this crate."
)]
#![cfg_attr(not(feature = "std"), no_std)]
pub use ::num_enum_derive::{FromPrimitive, IntoPrimitive, TryFromPrimitive, UnsafeFromPrimitive};
use ::core::fmt;
pub trait FromPrimitive: Sized {
type Primitive: Copy + Eq;
fn from_primitive(number: Self::Primitive) -> Self;
}
pub trait TryFromPrimitive: Sized {
type Primitive: Copy + Eq + fmt::Debug;
const NAME: &'static str;
fn try_from_primitive(number: Self::Primitive) -> Result<Self, TryFromPrimitiveError<Self>>;
}
#[derive(::derivative::Derivative)]
#[derivative( // use derivative to remove incorrect bound on `Enum` parameter. See https://github.com/rust-lang/rust/issues/26925
Debug(bound = ""),
Clone(bound = ""),
Copy(bound = ""),
PartialEq(bound = ""),
Eq(bound = "")
)]
pub struct TryFromPrimitiveError<Enum: TryFromPrimitive> {
pub number: Enum::Primitive,
}
impl<Enum: TryFromPrimitive> fmt::Display for TryFromPrimitiveError<Enum> {
fn fmt(self: &'_ Self, stream: &'_ mut fmt::Formatter<'_>) -> fmt::Result {
write!(
stream,
"No discriminant in enum `{name}` matches the value `{input:?}`",
name = Enum::NAME,
input = self.number,
)
}
}
#[cfg(feature = "std")]
impl<Enum: TryFromPrimitive> ::std::error::Error for TryFromPrimitiveError<Enum> {}