From 7f82a6f31e40e596a43939ab18d685a8f0b78d7b Mon Sep 17 00:00:00 2001
From: rich <rich>
Date: Thu, 25 Nov 2004 22:16:17 +0000
Subject: [PATCH] Added correct handling of undef.

---
 examples/test.ml |  7 ++++++-
 perl.ml          |  5 ++---
 perl_c.c         | 14 ++++++++++++--
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/examples/test.ml b/examples/test.ml
index 05d6042..490401e 100644
--- a/examples/test.ml
+++ b/examples/test.ml
@@ -1,6 +1,6 @@
 (* Simple test of the API.
  * Copyright (C) 2003 Merjis Ltd.
- * $Id: test.ml,v 1.6 2003-12-11 17:41:52 rich Exp $
+ * $Id: test.ml,v 1.7 2004-11-25 22:16:17 rich Exp $
  *)
 
 open Printf
@@ -48,5 +48,10 @@ let () =
   let sv = Perl.call_method obj "get_foo" [] in
   printf "TestClass.foo is %d\n" (Perl.int_of_sv sv); flush stdout;
 
+  (* Create an undef value and test it. *)
+  let undef = Perl.sv_undef () in
+  printf "sv_is_undef (undef) = %s\n"
+    (string_of_bool (Perl.sv_is_undef undef));
+
   (* Perform a full collection - good way to find GC/allocation bugs. *)
   Gc.full_major ()
diff --git a/perl.ml b/perl.ml
index a193446..cdbfa7c 100644
--- a/perl.ml
+++ b/perl.ml
@@ -1,6 +1,6 @@
 (* Interface to Perl from OCaml.
  * Copyright (C) 2003 Merjis Ltd.
- * $Id: perl.ml,v 1.11 2003-12-11 17:41:52 rich Exp $
+ * $Id: perl.ml,v 1.12 2004-11-25 22:16:17 rich Exp $
  *)
 
 type sv
@@ -26,6 +26,7 @@ external string_of_sv : sv -> string = "perl4caml_string_of_sv"
 external sv_of_string : string -> sv = "perl4caml_sv_of_string"
 external sv_is_true : sv -> bool = "perl4caml_sv_is_true"
 external sv_undef : unit -> sv = "perl4caml_sv_undef"
+external sv_is_undef : sv -> bool = "perl4caml_sv_is_undef"
 external sv_yes : unit -> sv = "perl4caml_sv_yes"
 external sv_no : unit -> sv = "perl4caml_sv_no"
 
@@ -47,8 +48,6 @@ type sv_t    = SVt_NULL
 	     | SVt_PVMG
 
 external sv_type : sv -> sv_t = "perl4caml_sv_type"
-let sv_is_undef sv =
-  SVt_NULL = sv_type sv
 
 let string_of_sv_t = function
     SVt_NULL  -> "SVt_NULL"
diff --git a/perl_c.c b/perl_c.c
index f11a2b5..4241534 100644
--- a/perl_c.c
+++ b/perl_c.c
@@ -1,6 +1,6 @@
 /* Interface to Perl from OCaml.
  * Copyright (C) 2003 Merjis Ltd.
- * $Id: perl_c.c,v 1.16 2004-11-03 14:15:18 rich Exp $
+ * $Id: perl_c.c,v 1.17 2004-11-25 22:16:17 rich Exp $
  */
 
 #include <stdio.h>
@@ -158,7 +158,17 @@ CAMLprim value
 perl4caml_sv_undef (value unit)
 {
   CAMLparam1 (unit);
-  CAMLreturn (Val_sv (newSV (0)));
+  /*CAMLreturn (Val_sv (newSV (0)));*/
+  CAMLreturn (Val_sv (&PL_sv_undef));
+}
+
+CAMLprim value
+perl4caml_sv_is_undef (value svv)
+{
+  CAMLparam1 (svv);
+  SV *sv = Sv_val (svv);
+  CAMLreturn (!SvPOK (sv) && !SvIOK (sv) && SvTYPE (sv) == SVt_NULL
+	      ? Val_true : Val_false);
 }
 
 CAMLprim value
-- 
1.8.3.1