From 823169f52e7e55d6b037d40be04569b46210c100 Mon Sep 17 00:00:00 2001
From: dishmaker <141624503+dishmaker@users.noreply.github.com>
Date: Tue, 7 Oct 2025 16:11:48 +0200
Subject: [PATCH 1/2] der: add docs for `Error` and `ErrorKind`

---
 der/src/error.rs | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/der/src/error.rs b/der/src/error.rs
index aeb10b8b9..6912f77cd 100644
--- a/der/src/error.rs
+++ b/der/src/error.rs
@@ -15,6 +15,22 @@ use crate::pem;
 pub type Result<T> = core::result::Result<T, Error>;
 
 /// Error type.
+///
+/// ## Example
+/// ```
+/// use der::{Decode, ErrorKind, Reader};
+///
+/// struct MyDecodable;
+///
+/// impl<'a> Decode<'a> for MyDecodable {
+///     type Error = der::Error;
+///
+///     fn decode<R: Reader<'a>>(reader: &mut R) -> Result<Self, der::Error> {
+///         // Error implements From<ErrorKind>
+///         Err(ErrorKind::OidMalformed.into())
+///     }
+/// }
+/// ```
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub struct Error {
     /// Kind of error.
@@ -162,6 +178,15 @@ impl From<time::error::ComponentRange> for Error {
 }
 
 /// Error type.
+///
+/// # Example
+/// ```
+/// use der::{asn1::OctetStringRef, Decode, ErrorKind};
+///
+/// let err = <&OctetStringRef>::from_der(&[0x04, 0x80, 0x00]).unwrap_err();
+///
+/// assert_eq!(err.kind(), ErrorKind::IndefiniteLength);
+/// ```
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 #[non_exhaustive]
 pub enum ErrorKind {

From 69940ded87c5a6a13703935e425965d2cb72050c Mon Sep 17 00:00:00 2001
From: dishmaker <141624503+dishmaker@users.noreply.github.com>
Date: Thu, 9 Oct 2025 15:23:26 +0200
Subject: [PATCH 2/2] der: reader.error(..) example

---
 der/src/error.rs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/der/src/error.rs b/der/src/error.rs
index 6912f77cd..215daf159 100644
--- a/der/src/error.rs
+++ b/der/src/error.rs
@@ -26,8 +26,7 @@ pub type Result<T> = core::result::Result<T, Error>;
 ///     type Error = der::Error;
 ///
 ///     fn decode<R: Reader<'a>>(reader: &mut R) -> Result<Self, der::Error> {
-///         // Error implements From<ErrorKind>
-///         Err(ErrorKind::OidMalformed.into())
+///         Err(reader.error(ErrorKind::OidMalformed))
 ///     }
 /// }
 /// ```