1 files changed, 56 insertions, 0 deletions
diff --git a/src/error/mod.rs b/src/error/mod.rs
new file mode 100644
index 0000000..26d9b4a
--- /dev/null
+++ b/src/error/mod.rs
@@ -0,0 +1,56 @@
+// Copyright 2022-2024 Gabriel Bjørnager Jensen.
+
+//! Error handling.
+
+use std::error::Error as StdError;
+use std::fmt::{Display, Formatter};
+
+/// Mapping of [`std::result::Result`].
+pub type Result<T> = std::result::Result<T, Error>;
+
+/// Denotes an error.
+///
+/// These variants are used when a deserialisation fails.
+/// Serialisations are assumed infallible.
+#[derive(Debug)]
+pub enum Error {
+	ArrayLengthMismatch { len: usize, ok_len: usize },
+
+	EndOfDStream { len: usize, ok_len: usize },
+
+	InvalidBoolean { value: u8 },
+
+	InvalidCodePoint { value: u32 },
+
+	NullInteger,
+}
+
+impl Display for Error {
+	fn fmt(&self, f: &mut Formatter) -> std::fmt::Result {
+		use Error::*;
+
+		match *self {
+			ArrayLengthMismatch { len, ok_len } => {
+				write!(f, "expected array of length ({ok_len}) but got ({len}) elements")
+			},
+
+			EndOfDStream { len, ok_len } => {
+				write!(f, "({ok_len}) byte(s) were requested but only ({len}) byte(s) were left")
+			},
+
+			InvalidBoolean { value } => {
+				write!(f, "expected boolean but got {value:#02X}")
+			},
+
+			InvalidCodePoint { value } => {
+				write!(f, "code point U+{value:04X} is not valid")
+			}
+
+			NullInteger => {
+				write!(f, "expected non-zero integer but got (0)")
+			},
+		}
+	}
+}
+
+impl StdError for Error { }