Now does the -s/--squeeze-blank option.

cat/main.go

@@ -16,9 +16,12 @@ func Fail(err error, format string, v ...any) {
 
 func main() {
   var number bool
+  var squeeze bool
 
   flag.BoolVar(&number, "n", false, "Number all nonempty output lines, starting with 1")
   flag.BoolVar(&number, "number", false, "Number all nonempty output lines, starting with 1")
+  flag.BoolVar(&squeeze, "s", false, "Suppress repeated adjacnet blank lines")
+  flag.BoolVar(&squeeze, "squeeze-blank", false, "Suppress repeated adjacnet blank lines")
   flag.Parse()
 
   if flag.NArg() < 1 {
@@ -34,6 +37,10 @@ func main() {
   if(number) {
     count := 1
     for line := range strings.Lines(string(in_file)) {
+      if squeeze && len(line) <= 1 {
+        continue
+      }
+
       fmt.Printf("%0.4d: %s", count, line)
       count++
     }