greatly simplify tictactoe now that we have for loops

README.md

@@ -1,7 +1,7 @@
 # grol-discord-bot
 Discord bot offering grol
 
-![screenshot](screenshot.png)
+![screenshot](https://github.com/user-attachments/assets/91687f8a-6023-4a8c-8564-865f054b2941)
 
 ## Invite link
 Invite link (add grol bot to your server):

discord.gr

@@ -2,6 +2,55 @@
    Library in grol for discord bot.
 */
 
+// --- General library functions ---
+
+// Note: some of these could be moved from recursive to iterative now that we have `for` loops.
+
+// f argument takes the element and the index
+func walk(f, a) {
+	(f,a,i) => {
+		if (len(a)==0) {
+			[]
+		} else {
+			[f(first(a),i)]+self(f,rest(a),i+1)
+		}
+	}(f,a,0)
+}
+
+// Convert to string
+func str(x) {sprintf("%v", x)}
+
+// Apply a function to each element of an array.
+func apply(f, a) {
+    if (len(a)==0) {
+        []
+    } else {
+        [f(first(a))]+apply(f,rest(a))
+    }
+}
+
+// Reverse an array or map or string
+func reverse(a) {
+    if len(a) == 0 {
+        return []
+    }
+    self(rest(a)) + first(a)
+}
+
+// Filter an array
+func filter(predicate, arr) {
+	if len(arr) == 0 {
+	  []
+	} else if predicate(first(arr)) {
+      [first(arr)] + filter(predicate, rest(arr))
+	} else {
+	  filter(predicate, rest(arr))
+	}
+}
+
+
+// ---- discord specific ----
+
 discord = {
   "actionRow": elems => {
 		{
@@ -74,6 +123,8 @@ discord = {
 	state.end = tictactoe.endGame(board)
 	if state.end != nil{
 		clicked = clicked + ": " + state.end + " wins!"
+	} else if state.turn >= 9 {
+		clicked = clicked + ": draw."
 	}
 	InteractionRespond({
 		"type": discord.interaction.update_message,
@@ -85,16 +136,8 @@ discord = {
 
 state = {}
 
-// f argument takes the element and the index
-func walk(f, a) {
-	(f,a,i) => {
-		if (len(a)==0) {
-			[]
-		} else {
-			[f(first(a),i)]+self(f,rest(a),i+1)
-		}
-	}(f,a,0)
-}
+// ---- tic tac toe ----
+
 
 tictactoe = {
   "empty_board": [["","",""],["","",""],["","",""]],
@@ -121,20 +164,14 @@ tictactoe = {
     },
   "endGame": board => {
 	// check for win
-	r = for(3, (i,r) => {
-		if r!=nil {
-			r
-		} else if board[i][0] != "" && board[i][0] == board[i][1] && board[i][1] == board[i][2] {
-			board[i][0]
+	for i=0:3 {
+		if board[i][0] != "" && board[i][0] == board[i][1] && board[i][1] == board[i][2] {
+			return board[i][0]
 		} else if board[0][i] != "" && board[0][i] == board[1][i] && board[1][i] == board[2][i] {
-			board[0][i]
-		} else {
-			nil
+			return board[0][i]
 		}
-	}, nil)
-	if r!=nil {
-		r
-	} else if board[0][0] != "" && board[0][0] == board[1][1] && board[1][1] == board[2][2] {
+	}
+	if board[0][0] != "" && board[0][0] == board[1][1] && board[1][1] == board[2][2] {
 		board[0][0]
 	} else if board[0][2] != "" && board[0][2] == board[1][1] && board[1][1] == board[2][0] {
 		board[0][2]
@@ -150,8 +187,15 @@ tictactoe = {
 	}
   },
   "play": (board, next) => {
-	wmove = max(walk((row,i) => max(walk((cell,j) => {
-		if cell == "" {
+	for i = 0:3 {
+		freeList = []
+		row = board[i]
+		for j = 0:3 {
+			cell = row[j]
+			if cell != "" {
+				continue
+			}
+			freeList = freeList + [[i,j]]
 			row[j] = next
 			board[i] = row
 			if tictactoe.endGame(board) != nil {
@@ -164,34 +208,21 @@ tictactoe = {
 				log("Loss by", next, "at", i, j)
 				return [i,j]
 			}
+			// restore board
+			row[j]=""
+			board[i]=row
 		}
-		nil
-	}, row)), board))
-	if wmove != nil {
-		wmove
-	} else {
-		// try middle move
-		if board[1][1] == "" {
-			[1,1]
-		} else if board[0][0] == "" {
-			[0,0]
-		} else if board[0][2] == "" {
-			[0,2]
-		} else if board[2][0] == "" {
-			[2,0]
-		} else if board[2][2] == "" {
-			[2,2]
-		} else if board[0][1] == "" {
-			[0,1]
-		} else if board[1][0] == "" {
-			[1,0]
-		} else if board[1][2] == "" {
-			[1,2]
-		} else {
-			[2,1]
-		}
-    }
-  }
+	}
+	if len(freeList) == 1 { // only one move left
+		return freeList[0]
+	}
+	// try middle move
+	if board[1][1] == "" {
+		return [1,1]
+	}
+	// random move
+	freeList[rand(len(freeList))]
+  },
 }
 
 func TicTacToe() {
@@ -204,47 +235,6 @@ func layout(){
 	println("Simple project layout [github.com/go-standard/project-layout](<https://github.com/go-standard/project-layout#project-layout>) - simple is good!")
 }
 
-func str(x) {sprintf("%v", x)}
-
-// Iterate n times with first argument i=0 to n-1 and passing the intermediate result as second argument.
-func for(n, f, start) {
-    (i,f,x) => { // internal lambda with the index param and intermediate result
-		if (i>=n) {
-			return x
-		}
-		r = f(i,x)
-       self(i+1, f,r)
-    }(0,f,start)
-}
-
-// Apply a function to each element of an array.
-func apply(f, a) {
-    if (len(a)==0) {
-        []
-    } else {
-        [f(first(a))]+apply(f,rest(a))
-    }
-}
-
-// Reverse an array
-func reverse(a) {
-    if len(a) == 0 {
-        return []
-    }
-    self(rest(a)) + first(a)
-}
-
-// Filter an array
-func filter(predicate, arr) {
-	if len(arr) == 0 {
-	  []
-	} else if predicate(first(arr)) {
-      [first(arr)] + filter(predicate, rest(arr))
-	} else {
-	  filter(predicate, rest(arr))
-	}
-}
-
 
 // Result of eval of this file is logged by bot.go Run(). confirm we reached the end without error.
 print("Imported discord grol library ok")

go.mod

@@ -8,7 +8,7 @@ require (
 	fortio.org/scli v1.15.2
 	fortio.org/version v1.0.4
 	github.com/bwmarrin/discordgo v0.28.1
-	grol.io/grol v0.60.0
+	grol.io/grol v0.62.0
 )
 
 // replace grol.io/grol => ../grol

go.sum

@@ -43,5 +43,5 @@ golang.org/x/sys v0.24.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-grol.io/grol v0.60.0 h1:pg724EX6rHk+vAP3UzNs8Z+rYt4vcBZKyDUxRwczaLo=
-grol.io/grol v0.60.0/go.mod h1:auvyNPGD+C1jMFsu+EkAVmXCjweP9qRLoTIYtdfrWiI=
+grol.io/grol v0.62.0 h1:frHwkLiL22mNxlMidSltOwrGN3eLYW+wXkQYy2uX+sg=
+grol.io/grol v0.62.0/go.mod h1:auvyNPGD+C1jMFsu+EkAVmXCjweP9qRLoTIYtdfrWiI=

main.go

@@ -14,7 +14,7 @@ import (
 var (
 	//go:embed discord.gr
 	libraryCode string
-	depth       = flag.Int("max-depth", 10000, "Maximum depth of recursion")
+	depth       = flag.Int("max-depth", 2500, "Maximum depth of recursion")
 	maxLen      = flag.Int("max-save-len", 2000, "Maximum len of saved identifiers, use 0 for unlimited")
 	panicF      = flag.Bool("panic", false, "Don't catch panic (DEV only)")
 )