Godot 4 code to extract sudoku puzzle from html table

sudoku-puzzle-extraction.gd

extends Control

func _on_button_pressed():
	var html: String = $Src.text
	# Find start of table
	var idx1 = html.find("boardtable")
	if idx1 > 0:
		var idx2 = html.find("</table", idx1)
		if idx2 > 0:
			var table = html.substr(idx1, idx2 - idx1)
			var lines = table.split("</td>")
			var nums = []
			for line in lines:
				nums.append(line[-1])
			var puzzle = nums.reduce(concat).replace(";", ".").rstrip(">")
			print(puzzle)

func concat(a, b):
	return a + b

We cut and paste the inner HTML code from https://www.sudokuwiki.org/Daily_Sudoku when using the browser developer tools via F12 when inspecting the Sudoku table code.

This Godot GDScript 4 code uses the reduce method on an array to do what the join method used to do in Godot 3.x