buffer module, replacing stacks. TODO: docs, fix parsing of "numbers tuple" in mkbfv (consumed by the conditional branch parser)

examples/stacks.csn

@@ -1,35 +1,35 @@
 (
-    (stack r0)
+    (mkbf r0)
 
-    (push @r0 1)
-    (push @r0 2)
+    (bfpush @r0 1)
+    (bfpush @r0 2)
 
-    (pop r1 @r0)
+    (bfpop r1 @r0)
     (cmp r1 2 (ne? (fault)))
 
-    (pop r1 @r0)
+    (bfpop r1 @r0)
     (cmp r1 1 (ne? (fault)))
 
     ; test reverse push
-    (push @r0 '🐈')
-    (push @r0 7)
-    (rpush @r0 8)
+    (bfpush @r0 '🐈')
+    (bfpush @r0 7)
+    (bfrpush @r0 8)
 
-    (pop r1 @r0)
+    (bfpop r1 @r0)
     (cmp r1 7 (ne? (fault)))
 
-    (pop r1 @r0)
+    (bfpop r1 @r0)
     (cmp r1 '🐈' (ne? (fault)))
 
-    (pop r1 @r0)
+    (bfpop r1 @r0)
     (cmp r1 8 (ne? (fault)))
 
     ; test reverse pop
 
-    (push @r0 1000)
-    (push @r0 2000)
+    (bfpush @r0 1000)
+    (bfpush @r0 2000)
 
-    (rpop r1 @r0)
+    (bfrpop r1 @r0)
     (cmp r1 1000 (ne? (fault)))
 
     (del @r0)

examples/stdio.csn

@@ -1,27 +1,47 @@
 (
-    ; we don't have strings yet 👌
-    (ld @stdout 'P') (ld @stdout 'r') (ld @stdout 'e') (ld @stdout 's') (ld @stdout 's') (ld @stdout ' ')
-    (ld @stdout 'q') (ld @stdout ' ')
-    (ld @stdout 't') (ld @stdout 'o') (ld @stdout ' ')
-    (ld @stdout 'q') (ld @stdout 'u') (ld @stdout 'i') (ld @stdout 't')
-    (ld @stdout '…') (ld @stdout ' ')
+    ; Create a table of strings
+    (sym TXT r7)
+    (def T_HELLO 0)
+    (def T_UNK 1)
+    (mkbf TXT)
+    (mkbfv r0 "*** Type ascii to uppercase. Press q to quit. ***\n")
+    (bfins @TXT T_HELLO r0)
+    (mkbfv r0 "🐈")
+    (bfins @TXT T_UNK r0)
+
+    ; Print string from the table
+    (bfrd r0 @TXT T_HELLO)
+    (call print r0)
+
+    (proc print str
+        ; Print string from a buffer
+        (sym ch r1) (sym pos r2)
+        (ld pos 0)
+        (:next)
+            (bfrd ch @str pos)
+            (ret.ov)
+            (ld @stdout ch)
+            (inc pos)
+        (j :next)
+    )
 
     (:loop)
-    (ld r0 @stdin)
+        (ld r0 @stdin)
 
-    ; exit by pressing 'q'
-    (cmp r0 'q'
-        (=? (ld @stdout '\n')
-            (halt)))
+        (cmp r0 'q'
+            (eq? (ld @stdout '\n')
+                 (halt)))
 
-    ; uppercase ASCII
-    (cmp r0 'a' (<? (j :badchar)))
-    (cmp r0 'z' (>? (j :badchar)))
-    (sub r0 ' ')
-    (ld @stdout r0)
+        ; uppercase ASCII
+        (cmp r0 'a' (<? (j :badchar)))
+        (cmp r0 'z' (>? (j :badchar)))
+        (sub r0 ' ')
+        (ld @stdout r0)
     (j :loop)
 
     (:badchar)
-    (ld @stdout '🐈') ; show a kitty if not ASCII
+        (ld @stdout r0)
+        (bfrd r0 @TXT T_UNK)
+        (call print r0)
     (j :loop)
 )