Document RowDecodingError

Author: groue

GRDB/Core/Row.swift

@@ -129,6 +129,10 @@ import Foundation
 ///
 /// - ``RowAdapter``
 ///
+/// ### Errors
+///
+/// - ``RowDecodingError``
+///
 /// ### Supporting Types
 ///
 /// - ``RowCursor``

GRDB/Core/RowDecodingError.swift

@@ -24,6 +24,14 @@ enum RowKey: Hashable, Sendable {
 }
 
 /// A decoding error thrown when decoding a database row.
+///
+/// For example:
+///
+/// ```swift
+/// let row = try Row.fetchOne(db, sql: "SELECT NULL AS name")!
+/// // RowDecodingError: could not decode String from database value NULL.
+/// let name = try row.decode(String.self, forColumn: "name")
+/// ```
 public struct RowDecodingError: Error {
     enum Impl {
         case keyNotFound(RowKey, Context)

README.md

@@ -4984,12 +4984,13 @@ try dbQueue.write { db in
 
 ## Error Handling
 
-GRDB can throw [DatabaseError](#databaseerror), [RecordError], or crash your program with a [fatal error](#fatal-errors).
+GRDB can throw [DatabaseError](#databaseerror), [RecordError], [RowDecodingError], or crash your program with a [fatal error](#fatal-errors).
 
 Considering that a local database is not some JSON loaded from a remote server, GRDB focuses on **trusted databases**. Dealing with [untrusted databases](#how-to-deal-with-untrusted-inputs) requires extra care.
 
 - [DatabaseError](#databaseerror)
 - [RecordError]
+- [RowDecodingError]
 - [Fatal Errors](#fatal-errors)
 - [How to Deal with Untrusted Inputs](#how-to-deal-with-untrusted-inputs)
 - [Error Log](#error-log)
@@ -5094,6 +5095,18 @@ do {
 ```
 
 
+### RowDecodingError
+
+📖 [`RowDecodingError`](https://swiftpackageindex.com/groue/GRDB.swift/documentation/grdb/rowdecodingerror)
+
+**RowDecodingError** is thrown when the application can not decode a value from a database row. For example:
+
+```swift
+let row = try Row.fetchOne(db, sql: "SELECT NULL AS name")!
+// RowDecodingError: could not decode String from database value NULL.
+let name = try row.decode(String.self, forColumn: "name")
+```
+
 ### Fatal Errors
 
 **Fatal errors notify that the program, or the database, has to be changed.**
@@ -6111,6 +6124,7 @@ This chapter has been superseded by [ValueObservation] and [DatabaseRegionObserv
 [persistence methods]: #persistence-methods
 [Persistence Methods and the `RETURNING` clause]: #persistence-methods-and-the-returning-clause
 [RecordError]: #recorderror
+[RowDecodingError]: #rowdecodingerror
 [Transactions and Savepoints]: https://swiftpackageindex.com/groue/GRDB.swift/documentation/grdb/transactions
 [`DatabaseQueue`]: https://swiftpackageindex.com/groue/GRDB.swift/documentation/grdb/databasequeue
 [Database queues]: https://swiftpackageindex.com/groue/GRDB.swift/documentation/grdb/databasequeue