Xml comments.

Linq/AsyncEnumerableExtensions.cs

@@ -7,8 +7,18 @@
 
 using Ecng.Common;
 
+/// <summary>
+/// The extensions for <see cref="IAsyncEnumerable{T}"/>.
+/// </summary>
 public static class AsyncEnumerableExtensions
 {
+	/// <summary>
+	/// Converts the <see cref="IAsyncEnumerable{T}"/> to the array.
+	/// </summary>
+	/// <typeparam name="T">The type of the elements of the <see cref="IAsyncEnumerable{T}"/>.</typeparam>
+	/// <param name="enu">The enumeration.</param>
+	/// <param name="cancellationToken">The cancellation token.</param>
+	/// <returns>The array of the elements of the <see cref="IAsyncEnumerable{T}"/>.</returns>
 	public static async ValueTask<T[]> ToArrayAsync2<T>(this IAsyncEnumerable<T> enu, CancellationToken cancellationToken)
 	{
 		if (enu is null)
@@ -22,6 +32,13 @@ public static async ValueTask<T[]> ToArrayAsync2<T>(this IAsyncEnumerable<T> enu
 		return [.. list];
 	}
 
+	/// <summary>
+	/// Gets the first element of the <see cref="IAsyncEnumerable{T}"/>.
+	/// </summary>
+	/// <typeparam name="T">The type of the elements of the <see cref="IAsyncEnumerable{T}"/>.</typeparam>
+	/// <param name="enu">The enumeration.</param>
+	/// <param name="cancellationToken">The cancellation token.</param>
+	/// <returns>The first element of the <see cref="IAsyncEnumerable{T}"/>.</returns>
 	public static async ValueTask<T> FirstAsync2<T>(this IAsyncEnumerable<T> enu, CancellationToken cancellationToken)
 	{
 		if (enu is null)
@@ -33,6 +50,13 @@ public static async ValueTask<T> FirstAsync2<T>(this IAsyncEnumerable<T> enu, Ca
 		throw new InvalidOperationException();
 	}
 
+	/// <summary>
+	/// Gets the first element of the <see cref="IAsyncEnumerable{T}"/> or the default value if the enumeration is empty.
+	/// </summary>
+	/// <typeparam name="T">The type of the elements of the <see cref="IAsyncEnumerable{T}"/>.</typeparam>
+	/// <param name="enu">The enumeration.</param>
+	/// <param name="cancellationToken">The cancellation token.</param>
+	/// <returns>The first element of the <see cref="IAsyncEnumerable{T}"/> or the default value if the enumeration is empty.</returns>
 	public static async ValueTask<T> FirstOrDefaultAsync2<T>(this IAsyncEnumerable<T> enu, CancellationToken cancellationToken)
 	{
 		if (enu is null)

Linq/ExpressionExtensions.cs

@@ -7,11 +7,25 @@
 
 	using Ecng.Common;
 
+	/// <summary>
+	/// The extensions for <see cref="Expression"/>.
+	/// </summary>
 	public static class ExpressionExtensions
 	{
+		/// <summary>
+		/// Gets the constant value from the expression.
+		/// </summary>
+		/// <typeparam name="T">The type of the constant value.</typeparam>
+		/// <param name="e">The expression.</param>
+		/// <returns>The constant value.</returns>
 		public static T GetConstant<T>(this Expression e)
 			=> ((ConstantExpression)e).Value.To<T>();
 
+		/// <summary>
+		/// Evaluates the expression and returns its value.
+		/// </summary>
+		/// <param name="e">The expression to evaluate.</param>
+		/// <returns>The evaluated value.</returns>
 		public static object Evaluate(this Expression e)
 		{
 			//A little optimization for constant expressions
@@ -21,6 +35,12 @@ public static object Evaluate(this Expression e)
 			return Expression.Lambda(e).Compile().DynamicInvoke();
 		}
 
+		/// <summary>
+		/// Replaces the source provider in the expression with the specified query provider.
+		/// </summary>
+		/// <param name="expression">The expression to modify.</param>
+		/// <param name="provider">The query provider to set.</param>
+		/// <exception cref="ArgumentNullException">Thrown when expression or provider is null.</exception>
 		public static void ReplaceSource(this Expression expression, IQueryProvider provider)
 		{
 			if (expression is null)
@@ -36,6 +56,11 @@ public static void ReplaceSource(this Expression expression, IQueryProvider prov
 			field.SetValue(expression, provider);
 		}
 
+		/// <summary>
+		/// Removes quote expressions from the given expression.
+		/// </summary>
+		/// <param name="e">The expression to process.</param>
+		/// <returns>The unquoted expression.</returns>
 		public static Expression StripQuotes(this Expression e)
 		{
 			while (e.NodeType == ExpressionType.Quote)
@@ -46,6 +71,13 @@ public static Expression StripQuotes(this Expression e)
 			return e;
 		}
 
+		/// <summary>
+		/// Gets the value of the specified member from the given instance.
+		/// </summary>
+		/// <param name="member">The member whose value to retrieve.</param>
+		/// <param name="instance">The object instance from which to retrieve the value.</param>
+		/// <returns>The value of the member.</returns>
+		/// <exception cref="NotSupportedException">Thrown when the member type is not supported.</exception>
 		public static object GetMemberValue(this MemberInfo member, object instance)
 		{
 			if (member is PropertyInfo pi)
@@ -56,6 +88,11 @@ public static object GetMemberValue(this MemberInfo member, object instance)
 				throw new NotSupportedException();
 		}
 
+		/// <summary>
+		/// Retrieves the innermost member in a nested member expression.
+		/// </summary>
+		/// <param name="exp">The member expression to process.</param>
+		/// <returns>The innermost member expression.</returns>
 		public static MemberExpression GetInnerMember(this MemberExpression exp)
 		{
 			if (exp.Expression is MemberExpression d)
@@ -64,6 +101,14 @@ public static MemberExpression GetInnerMember(this MemberExpression exp)
 			return exp;
 		}
 
+		/// <summary>
+		/// Evaluates the expression and returns its value as the specified type.
+		/// </summary>
+		/// <typeparam name="TValue">The type to convert the evaluated value to.</typeparam>
+		/// <param name="exp">The expression to evaluate.</param>
+		/// <returns>The evaluated value converted to the specified type.</returns>
+		/// <exception cref="ArgumentNullException">Thrown when the expression is null.</exception>
+		/// <exception cref="ArgumentOutOfRangeException">Thrown when the expression type is not supported.</exception>
 		public static TValue GetValue<TValue>(this Expression exp)
 		{
 			if (exp is null)
@@ -77,6 +122,12 @@ public static TValue GetValue<TValue>(this Expression exp)
 			throw new ArgumentOutOfRangeException(exp.NodeType.ToString());
 		}
 
+		/// <summary>
+		/// Converts the given expression type to its equivalent <see cref="ComparisonOperator"/>.
+		/// </summary>
+		/// <param name="type">The expression type.</param>
+		/// <returns>The corresponding <see cref="ComparisonOperator"/>.</returns>
+		/// <exception cref="ArgumentOutOfRangeException">Thrown when the expression type has no corresponding operator.</exception>
 		public static ComparisonOperator ToOperator(this ExpressionType type)
 		{
 			return type switch