js: codegen & vlib fixes, replace the Game of Life CLI example (#12272)

examples/game_of_life/life.v

@@ -1,25 +1,85 @@
-module main
-
+import term
+import rand
 import time
-import automaton
 
-fn print_automaton(a &automaton.Automaton) {
-	for y := 1; y < a.field.maxy; y++ {
-		mut s := '    '
-		for x := 1; x < a.field.maxx; x++ {
-			cell := a.field.get(x, y)
-			s += if cell == 1 { '@' } else { '.' }
-		}
-		println(s)
+const (
+	cell     = '█'
+	nothing  = ' '
+	switches = {
+		cell:    nothing
+		nothing: cell
 	}
-	println('')
+	transformers = [nothing, cell]
+)
+
+struct Game {
+mut:
+	grid [][]string
+}
+
+fn (g Game) get_surrounding_alive_count(x int, y int) int {
+	mut count := 0
+	for i := x - 1; i <= x + 1; i++ {
+		for j := y - 1; j <= y + 1; j++ {
+			if (i != x || j != y) && i >= 0 && j >= 0 && i < g.grid.len && j < g.grid[x].len {
+				if g.grid[i][j] == cell {
+					count++
+				}
+			}
+		}
+	}
+	return count
+}
+
+fn (mut g Game) evolve() {
+	mut temp_grid := [][]string{}
+	for x in 0 .. g.grid.len {
+		temp_grid << []string{}
+		for y in 0 .. g.grid[x].len {
+			count := g.get_surrounding_alive_count(x, y)
+			if count == 3 || ((g.grid[x][y] == cell) && count == 2) {
+				temp_grid[x] << cell
+			} else {
+				temp_grid[x] << nothing
+			}
+		}
+	}
+
+	g.grid = temp_grid
+}
+
+fn (mut g Game) display() {
+	for y in 0 .. g.grid[0].len {
+		mut line := ''
+		for x in 0 .. g.grid.len {
+			line += g.grid[x][y]
+		}
+		println(line)
+	}
+}
+
+fn new_game() Game {
+	w, h := term.get_terminal_size()
+	mut grid := [][]string{}
+	for x in 0 .. w {
+		grid << []string{}
+		for _ in 0 .. h {
+			is_live := rand.f64() > 0.82
+			icon := transformers[int(is_live)]
+			grid[x] << icon
+		}
+	}
+	return Game{grid}
 }
 
 fn main() {
-	mut a := automaton.gun()
+	mut g := new_game()
+
+	g.display()
 	for {
-		a.update()
-		print_automaton(a)
+		g.evolve()
+		term.erase_clear()
+		g.display()
 		time.sleep(100 * time.millisecond)
 	}
 }