Add package zarith.top with REPL printer

Fix ocaml#17

META

@@ -3,3 +3,14 @@ requires = ""
 version = "1.5"
 archive(byte) = "zarith.cma"
 archive(native) = "zarith.cmxa"
+
+package "top" (
+  version = "1.5"
+  description = "ZArith toplevel support"
+  requires = "zarith"
+  archive(byte) = "zarith_top.cma"
+  archive(native) = "zarith_top.cmxa"
+  plugin(byte) = "zarith_top.cma"
+  plugin(native) = "zarith_top.cmxs"
+  exists_if = "zarith_top.cma"
+)

project.mak

@@ -42,12 +42,16 @@ CMIOBJ = $(MLISRC:%.mli=%.cmi)
 CMXOBJ = $(MLISRC:%.mli=%.cmx)
 CMIDOC = $(MLISRC:%.mli=%.cmti)
 
-TOINSTALL := zarith.h zarith.cma libzarith.$(LIBSUFFIX) $(MLISRC) $(CMIOBJ)
+TOINSTALL := zarith.h zarith.cma libzarith.$(LIBSUFFIX) $(MLISRC) $(CMIOBJ) \
+  zarith_top.cma
 
 ifeq ($(HASOCAMLOPT),yes)
 TOINSTALL += zarith.$(LIBSUFFIX) zarith.cmxa $(CMXOBJ)
 endif
 
+OCAMLFLAGS = -I +compiler-libs
+OCAMLOPTFLAGS = -I +compiler-libs
+
 ifeq ($(HASDYNLINK),yes)
 TOINSTALL += zarith.cmxs
 endif
@@ -77,6 +81,9 @@ zarith.cmxs: zarith.cmxa libzarith.$(LIBSUFFIX)
 libzarith.$(LIBSUFFIX) dllzarith.$(DLLSUFFIX): $(SSRC:%.S=%.$(OBJSUFFIX)) $(CSRC:%.c=%.$(OBJSUFFIX)) 
 	$(OCAMLMKLIB) -failsafe -o zarith $+ $(LIBS)
 
+zarith_top.cma: zarith_top.cmo
+	$(OCAMLC) -o $@ -a $<
+
 doc: $(MLISRC)
 	mkdir -p html
 	$(OCAMLDOC) -html -d html -charset utf8 $+

zarith_top.ml

@@ -0,0 +1,14 @@
+open Printf
+
+let eval_string
+      ?(print_outcome = false) ?(err_formatter = Format.err_formatter) str =
+  let lexbuf = Lexing.from_string str in
+  let phrase = !Toploop.parse_toplevel_phrase lexbuf in
+  Toploop.execute_phrase print_outcome err_formatter phrase
+
+let () =
+  let printers = ["Z.pp_print"; "Q.pp_print"] in
+  let ok = List.fold_left (fun b p ->
+               b && eval_string(sprintf "#install_printer %s;;" p))
+      true printers in
+  if not ok then Format.eprintf "Problem installing ZArith-printers@."