error: Add thiserror

src/error-handling/thiserror.md

@@ -1 +1,30 @@
-# thiserror
+# thiserror 库
+
+这个库用于快速给结构体或者枚举实现 `Error` trait.
+
+使用方法极为简单:
+
+```rust
+use thiserror::Error;
+
+#[derive(Error, Debug)]
+pub enum DataStoreError {
+    #[error("data store disconnected")]
+    Disconnect(#[from] io::Error),
+    #[error("the data for key `{0}` is not available")]
+    Redaction(String),
+    #[error("invalid header (expected {expected:?}, found {found:?})")]
+    InvalidHeader {
+        expected: String,
+        found: String,
+    },
+    #[error("unknown data store error")]
+    Unknown,
+}
+```
+
+它会根据宏定义, 自动为结构体实现 `Display` trait.
+
+## 参考
+
+- [thiserror document](https://docs.rs/thiserror/latest/thiserror/)