Inital post-execution draft

docs/guides/commands/post-execution.md

@@ -0,0 +1,41 @@
+# Preface
+
+When developing a command system or modules, you may want to consider
+building a post-execution handling system so you can have a finer 
+control over commands. Discord.NET offers several different 
+post-execution workflow for you to work with.
+
+If you recall, in the [Command Guide], we've shown the following 
+example for executing and handling commands,
+
+[!code[Command Handler](samples/command_handler.cs)]
+
+You may notice that after we perform [ExecuteAsync], we store the 
+result and print it to the chat. This is essentially the most
+basic post-execution handling. With this in mind, we could start doing
+things like the following,
+
+[!code[Basic Command Handler](samples/post-execution_basic.cs)]
+
+**But!** This may not always be preferred, because you are 
+creating your  post-execution logic *with* the essential command 
+handler. This could lead to messy code and has another potential 
+issue, working with `RunMode.Async`.
+
+If your command is marked with `RunMode.Async`, [ExecuteAsync] will 
+return a successful [ExecuteResult] instead of whatever results 
+the actual command may return. Because of the way `RunMode.Async` 
+[works](../../faq/commands.md), handling within the command handler 
+may not always achieve the desired effect.
+
+## CommandExecuted Event
+
+Enter [CommandExecuted], an event that was introduced in 
+Discord.NET 2.0. This event is raised **when the command is 
+sucessfully executed** and is not prone to `RunMode.Async`'s 
+[ExecuteAsync] drawbacks.
+
+[CommandExecuted]: xref:Discord.Commands.CommandService.CommandExecuted
+[ExecuteAsync]: xref:Discord.Commands.CommandService.ExecuteAsync*
+[ExecuteResult]: xref:Discord.Commands.ExecuteResult
+[Command Guide]: Commands.md

docs/guides/commands/samples/post-execution_basic.cs

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+var result = await _commands.ExecuteAsync(context, argPos, _services);
+if (result.CommandError != null)
+	switch(result.CommandError)
+	{
+		case CommandError.BadArgCount:
+			await context.Channel.SendMessageAsync("Parameter count does not match any command's.");
+			break;
+		default:
+			await context.Channel.SendMessageAsync($"An error has occurred {result.ErrorReason}");
+			break;
+	}

docs/guides/toc.yml

@@ -20,6 +20,8 @@
   items:
     - name: Command Guide
       href: commands/commands.md
+    - name: Post-execution Handling
+      href: commands/post-execution.md
 - name: Voice
   items:
     - name: Voice Guide