Data update

Task/Comma-quibbling/Dc/comma-quibbling.dc

@@ -0,0 +1,32 @@
+[(q)uibble: main entry point. print brackets, calling n in between if stack not
+ empty.]sx
+[ [{]n z 0 !=n [}]pR ]sq
+
+[(n)onempty: if more than 1 item, call m. then print top of stack.]sx
+[ z 1 !=m n ]sn
+
+[(m)ore: call f to flip stack into r register, call p to print most of it,
+ then pop the last item back onto the main stack so it's there to be printed
+ after we return]sx
+[ lfx lpx Lr ]sm
+
+[(f)lip: utility routine to reverse the stack into the r register]sx
+[ Sr z 0 !=f ]sf
+
+[(p)rint: get next item from stack in r register and print it. If there are
+ more than 2 items left on the register stack (which never drops below one
+ item), print a comma (c) and recurse. If there are exactly two items left,
+ print " and " (a) and return.]sx
+[ Lr n 2 yr >c 2 yr =a 2 yr >p]sp
+
+[(c)omma: utility routine to print a comma followed by a space]sx
+[ [, ]n ]sc
+
+[(a)and: utility routine to  print " and "]sx
+[ [ and ]n ]sa
+
+[run tests]sx
+lqx
+[ABC] lqx
+[ABC] [DEF] lqx
+[ABC] [DEF] [G] [H] lqx