many thanks for Araq's advise!

examples/fizzbuzz.nim

@@ -1,16 +1,14 @@
 # Fizz Buzz program
 
-var f = "Fizz"
-var b = "Buzz"
+const f = "Fizz"
+const b = "Buzz"
 for i in 1..100:
-  if i mod 15 == 0:
-    echo f & b
-    continue
-  if i mod 5 == 0:
-    echo b
-    continue
   if i mod 3 == 0:
     echo f
-    continue
-  echo i
+  elif i mod 5 == 0:
+    echo b
+  elif i mod 15 == 0:
+    echo f, b
+  else:
+    echo i