ADDED   test.d
Index: test.d
==================================================================
--- test.d
+++ test.d
@@ -0,0 +1,130 @@
+import std.algorithm;
+import std.array;
+import std.conv;
+import std.stdio;
+import std.string;
+
+class Map
+{
+	private char[][] data;
+
+	this(File input)
+	{
+		foreach(s; input.byLine())
+			data ~= s.chomp.dup;
+
+		int width = 0;
+		foreach(s; data)
+			width = max(width, s.length);
+
+		// space padding and sentinels
+		foreach(ref s; data) {
+			int p = s.length;
+			s.length = width;
+			s[p..$] = ' ';
+			s = '#' ~ s ~ '#';
+		}
+
+		// vertical sentinel
+		char[] sen = new char[width+2];
+		sen[] = '#';
+		data = sen.dup ~ data ~ sen;
+	}
+
+	@property const
+	{
+		int W() { return data[0].length; }
+		int H() { return data.length; }
+		string toString() {
+			string result;
+			foreach(i,s; data) {
+				if(i) result ~= '\n';
+				result ~= s.idup;
+			}
+			return result;
+		}
+	}
+
+	void command_R() { move(0, +1); }
+	void command_L() { move(0, -1); }
+	void command_U() { move(-1, 0); }
+	void command_D() { move(+1, 0); }
+	void wait() { update(); }
+
+	void move(int dy, int dx) {
+		foreach(y,s; data)
+		foreach(x,c; s)
+			if(c == 'R')
+				return move(dy, dx, y, x);
+	}
+
+	void move(int dy, int dx, int y, int x) {
+		if(data[y+dy][x+dx]==' ' || data[y+dy][x+dx]=='.'
+		   || data[y+dy][x+dx]=='\\' || data[y+dy][x+dx]=='O') {
+			data[y][x]=' ';
+			data[y+dy][x+dx]='R';
+		} else if(dy==0 && data[y+dy][x+dx]=='*' && data[y+2*dy][x+2*dx]==' ') {
+			data[y][x]=' ';
+			data[y+dy][x+dx]='R';
+			data[y+2*dy][x+2*dx]='*';
+		}
+		update();
+	}
+
+	void update() {
+		char[][] next;
+		foreach(y,s; data)
+			next ~= s.dup;
+
+		bool lambda = false;
+		for(int y=1; y+1<H; ++y)
+		for(int x=1; x+1<W; ++x)
+			lambda |= (data[y][x] == '\\');
+
+		for(int y=1; y+1<H; ++y)
+		for(int x=1; x+1<W; ++x) {
+			if(data[y][x]=='*') {
+				if(data[y+1][x]==' ') {
+					next[y][x]=' ';
+					next[y+1][x]='*';
+				}
+				else if(data[y+1][x]=='*' && data[y][x+1]==' ' && data[y+1][x+1]==' ') {
+					next[y][x]=' ';
+					next[y+1][x+1]='*';
+				}
+				else if(data[y+1][x]=='*' && data[y][x-1]==' ' && data[y+1][x-1]==' ') {
+					next[y][x]=' ';
+					next[y+1][x-1]='*';
+				}
+				else if(data[y+1][x]=='\\' && data[y][x+1]==' ' && data[y+1][x+1]==' ') {
+					next[y][x]=' ';
+					next[y+1][x+1]='*';
+				}
+			}
+			else if(data[y][x]=='L') {
+				if(!lambda)
+					next[y][x] = 'O';
+			}
+		}
+		data = next;
+	}
+}
+
+void main(string[] args)
+{
+	Map m = new Map(File(args[1]));
+	for(;;) {
+		writeln(m);
+		write("> ");
+		string s = readln();
+		if(s.length == 0)
+			break;
+		s = s.chomp().toUpper();
+		if(s=="R")m.command_R();
+		if(s=="L")m.command_L();
+		if(s=="U")m.command_U();
+		if(s=="D")m.command_D();
+		if(s=="W")m.wait();
+	}
+
+}