Mark all Parsing code as depricated

Author: Rosuavio

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Constants.cs

@@ -0,0 +1,7 @@
+namespace Microsoft.Toolkit.Parsers
+{
+    internal static class Constants
+    {
+        internal const string ParserObsoleteMsg = "Parsing code has been deprecated.";
+    }
+}

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Core/IParser.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Collections.Generic;
 
 namespace Microsoft.Toolkit.Parsers
@@ -10,6 +11,7 @@ namespace Microsoft.Toolkit.Parsers
     /// Parser interface.
     /// </summary>
     /// <typeparam name="T">Type to parse into.</typeparam>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public interface IParser<out T>
         where T : SchemaBase
     {

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Core/ParseHelpers.cs

@@ -2,11 +2,14 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+
 namespace Microsoft.Toolkit.Parsers.Core
 {
     /// <summary>
     /// This class offers helpers for Parsing.
     /// </summary>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public static class ParseHelpers
     {
         /// <summary>

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Core/SchemaBase.cs

@@ -2,11 +2,14 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+
 namespace Microsoft.Toolkit.Parsers
 {
     /// <summary>
     /// Strong typed schema base class.
     /// </summary>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public abstract class SchemaBase
     {
         /// <summary>

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Core/StringValueAttribute.cs

@@ -10,6 +10,7 @@ namespace Microsoft.Toolkit.Parsers.Core
     /// The StringValue attribute is used as a helper to decorate enum values with string representations.
     /// </summary>
     [AttributeUsage(AttributeTargets.Field)]
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public sealed class StringValueAttribute : Attribute
     {
         /// <summary>

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Markdown/Blocks/CodeBlock.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Text;
 using Microsoft.Toolkit.Parsers.Markdown.Helpers;
 
@@ -11,6 +12,7 @@ namespace Microsoft.Toolkit.Parsers.Markdown.Blocks
     /// Represents a block of text that is displayed in a fixed-width font.  Inline elements and
     /// escape sequences are ignored inside the code block.
     /// </summary>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public class CodeBlock : MarkdownBlock
     {
         /// <summary>

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Markdown/Blocks/HeaderBlock.cs

@@ -14,6 +14,7 @@ namespace Microsoft.Toolkit.Parsers.Markdown.Blocks
     /// <seealso href="https://spec.commonmark.org/0.29/#atx-headings">Single-Line Header CommonMark Spec</seealso>
     /// <seealso href="https://spec.commonmark.org/0.29/#setext-headings">Two-Line Header CommonMark Spec</seealso>
     /// </summary>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public class HeaderBlock : MarkdownBlock
     {
         /// <summary>

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Markdown/Blocks/HorizontalRuleBlock.cs

@@ -2,13 +2,15 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using Microsoft.Toolkit.Parsers.Core;
 
 namespace Microsoft.Toolkit.Parsers.Markdown.Blocks
 {
     /// <summary>
     /// Represents a horizontal line.
     /// </summary>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public class HorizontalRuleBlock : MarkdownBlock
     {
         /// <summary>

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Markdown/Blocks/LinkReferenceBlock.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using Microsoft.Toolkit.Parsers.Core;
 using Microsoft.Toolkit.Parsers.Markdown.Inlines;
 
@@ -10,6 +11,7 @@ namespace Microsoft.Toolkit.Parsers.Markdown.Blocks
     /// <summary>
     /// Represents the target of a reference ([ref][]).
     /// </summary>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public class LinkReferenceBlock : MarkdownBlock
     {
         /// <summary>

Microsoft.Toolkit.Uwp.UI.Controls.Markdown/Parsers/Markdown/Blocks/List/ListItemBlock.cs

@@ -2,13 +2,15 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Collections.Generic;
 
 namespace Microsoft.Toolkit.Parsers.Markdown.Blocks
 {
     /// <summary>
     /// This specifies the Content of the List element.
     /// </summary>
+    [Obsolete(Constants.ParserObsoleteMsg)]
     public class ListItemBlock
     {
         /// <summary>