command & readme

Author: T0shik

README.md

@@ -26,4 +26,6 @@ Full Playlist can be found [here](https://www.youtube.com/playlist?list=PLOeFnOV
 ### Behavioral Patterns
 
 - [Iterator](https://youtu.be/Gco6zF_ygSc)
+- [Interpreter](https://youtu.be/Vc3aiaAcIME)
 - [Chain of Responsibility](https://youtu.be/YQ03IyRu1Zo)
+- [Command](https://youtu.be/nW2ahdZojho)

command/canvas.linq

@@ -0,0 +1,65 @@
+<Query Kind="Program" />
+
+void Main()
+{
+
+}
+public class Canvas
+{
+
+}
+
+public interface Command
+{
+	void Execute(Canvas canvas);
+}
+
+public class Tool
+{
+	static string state;
+
+	public static Command GetCommand()
+	{
+		if (state == "brush")
+			return new Brush();
+		if (state == "erase")
+			return new Erase();
+		if (state == "fill")
+			return new Fill();
+
+		return null;
+	}
+}
+
+public class Brush : Command
+{
+	public void Execute(Canvas canvas)
+	{
+		// perform action on the canvas
+	}
+}
+
+public class Erase : Command
+{
+	public void Execute(Canvas canvas)
+	{
+		// perform action on the canvas
+	}
+}
+
+public class Fill : Command
+{
+	public void Execute(Canvas canvas)
+	{
+		// perform action on the canvas
+	}
+}
+
+
+
+Canvas canvas;
+
+public void Click()
+{
+	Tool.GetCommand().Execute(canvas);
+}

command/simple.linq

@@ -0,0 +1,47 @@
+<Query Kind="Program" />
+
+void Main()
+{
+	
+}
+
+interface Command {
+	void Execute();
+}
+
+class HighlightText : Command {
+
+	// text is the reciever
+	public HighlightText(string text)
+	{
+		
+	}
+
+	public void Execute()
+	{
+		// highlight text range
+	}
+}
+
+class BoldText : Command
+{
+	// text is the reciever
+	public BoldText(string text)
+	{
+
+	}
+
+	public void Execute()
+	{
+		// make text range bold
+	}
+}
+
+// button is the the decoupling
+// we don't know about the operation or the reciever
+class Button {
+	Command command;
+	public Button(Command command) => this.command = command;
+	
+	public void Click() => command.Execute();
+}

command/undoable.linq

@@ -0,0 +1,68 @@
+<Query Kind="Program" />
+
+void Main()
+{
+
+}
+
+interface Command
+{
+	void Execute();
+	void Undo();
+}
+
+public class HighlightConfig
+{
+	public int Colour { get; set; }
+	public int Height { get; set; }
+} 
+
+class HighlightText : Command
+{
+
+	// text is the reciever
+	// config is some singleton holding the state of the colour tool
+	public HighlightText(string text, HighlightConfig config)
+	{
+
+	}
+
+	public void Execute()
+	{
+		// highlight text range
+	}
+
+	public void Undo()
+	{
+		// un-highlight text range
+	}
+}
+
+class BoldText : Command
+{
+	// text is the reciever
+	public BoldText(string text)
+	{
+
+	}
+
+	public void Execute()
+	{
+		// make text range bold
+	}
+
+	public void Undo()
+	{
+		// un-highlight text range
+	}
+}
+
+// button is the the decoupling
+// we don't know about the operation or the reciever
+class Button
+{
+	Command command;
+	public Button(Command command) => this.command = command;
+
+	public void Click() => command.Execute();
+}

command/when_no_arguments.linq

@@ -0,0 +1,65 @@
+<Query Kind="Program" />
+
+void Main()
+{
+	var textContext = new TextContext();
+	var c1 = new DynamicCommand<TextContext>(textContext, tc => tc.HighlightText());
+	var c2 = new DynamicCommand<TextContext>(textContext, tc => tc.BoldText());
+	
+	// via reflection:
+	// typeof(TextContext).GetMethod("HighlightText").Invoke(textContext, null);
+}
+
+public class HighlightConfig
+{
+	public int Colour { get; set; }
+	public int Height { get; set; }
+}
+
+public class TextContext
+{
+	public void HighlightText()
+	{
+
+		// highlight text range
+	}
+
+	public void BoldText()
+	{
+		// make text range bold
+	}
+}
+
+
+interface ICommand
+{
+	void Execute();
+}
+
+
+class DynamicCommand<T> : ICommand
+{
+	T reciever;
+	Action<T> action;
+	public DynamicCommand(T reciever, Action<T> action)
+	{
+		this.reciever = reciever;
+		this.action = action;
+	}
+
+	public void Execute()
+	{
+		action(reciever);
+	}
+}
+
+
+// button is the the decoupling
+// we don't know about the operation or the reciever
+class Button
+{
+	ICommand command;
+	public Button(ICommand command) => this.command = command;
+
+	public void Click() => command.Execute();
+}

command/with_arguments.linq

@@ -0,0 +1,57 @@
+<Query Kind="Program" />
+
+void Main()
+{
+
+}
+
+interface Command
+{
+	void Execute();
+}
+
+public class HighlightConfig
+{
+	public int Colour { get; set; }
+	public int Height { get; set; }
+} 
+
+class HighlightText : Command
+{
+
+	// text is the reciever
+	// config is some singleton holding the state of the colour tool
+	public HighlightText(string text, HighlightConfig config)
+	{
+
+	}
+
+	public void Execute()
+	{
+		// highlight text range
+	}
+}
+
+class BoldText : Command
+{
+	// text is the reciever
+	public BoldText(string text)
+	{
+
+	}
+
+	public void Execute()
+	{
+		// make text range bold
+	}
+}
+
+// button is the the decoupling
+// we don't know about the operation or the reciever
+class Button
+{
+	Command command;
+	public Button(Command command) => this.command = command;
+
+	public void Click() => command.Execute();
+}