Change `defined?' to accept a module as its second argument.

Reported by Daniel Kraft <d@domob.eu>.

* doc/ref/api-binding.texi (Binding Reflection): Update documentation of
  `defined?'.

* libguile/evalext.c (scm_defined_p): Expect a module as the second
  argument, not a lexical environment.

2 files changed, 21 insertions, 41 deletions

diff --git a/doc/ref/api-binding.texi b/doc/ref/api-binding.texi
index b42f5567f..e53c48040 100644
--- a/doc/ref/api-binding.texi
+++ b/doc/ref/api-binding.texi
@@ -1,6 +1,6 @@
 @c -*-texinfo-*-
 @c This is part of the GNU Guile Reference Manual.
-@c Copyright (C)  1996, 1997, 2000, 2001, 2002, 2003, 2004
+@c Copyright (C)  1996, 1997, 2000, 2001, 2002, 2003, 2004, 2009
 @c   Free Software Foundation, Inc.
 @c See the file guile.texi for copying conditions.
 
@@ -271,10 +271,16 @@ with duplicate bindings.
 Guile provides a procedure for checking whether a symbol is bound in the
 top level environment.
 
-@c NJFIXME explain [env]
-@deffn {Scheme Procedure} defined? sym [env]
-@deffnx {C Function} scm_defined_p (sym, env)
-Return @code{#t} if @var{sym} is defined in the lexical environment @var{env}.  When @var{env} is not specified, look in the top-level environment as defined by the current module.
+@deffn {Scheme Procedure} defined? sym [module]
+@deffnx {C Function} scm_defined_p (sym, module)
+Return @code{#t} if @var{sym} is defined in the module @var{module} or
+the current module when @var{module} is not specified; otherwise return
+@code{#f}.
+
+Up to Guile 1.8, the second optional argument had to be @dfn{lexical
+environment} as returned by @code{the-environment}, for example.  The
+behavior of this function remains unchanged when the second argument is
+omitted.
 @end deffn
 
 
diff --git a/libguile/evalext.c b/libguile/evalext.c
index 56f74e213..19d8f2e02 100644
--- a/libguile/evalext.c
+++ b/libguile/evalext.c
@@ -31,49 +31,23 @@
 #include "libguile/evalext.h"
 
 SCM_DEFINE (scm_defined_p, "defined?", 1, 1, 0,
-            (SCM sym, SCM env),
-	    "Return @code{#t} if @var{sym} is defined in the lexical "
-	    "environment @var{env}.  When @var{env} is not specified, "
-	    "look in the top-level environment as defined by the "
-	    "current module.")
+            (SCM sym, SCM module),
+	    "Return @code{#t} if @var{sym} is defined in the module "
+	    "@var{module} or the current module when @var{module} is not"
+	    "specified.")
 #define FUNC_NAME s_scm_defined_p
 {
   SCM var;
 
   SCM_VALIDATE_SYMBOL (1, sym);
 
-  if (SCM_UNBNDP (env))
-    var = scm_sym2var (sym, scm_current_module_lookup_closure (),
-			 SCM_BOOL_F);
+  if (SCM_UNBNDP (module))
+    module = scm_current_module ();
   else
-    {
-      SCM frames = env;
-      register SCM b;
-      for (; SCM_NIMP (frames); frames = SCM_CDR (frames))
-	{
-	  SCM_ASSERT (scm_is_pair (frames), env, SCM_ARG2, FUNC_NAME);
-	  b = SCM_CAR (frames);
-	  if (scm_is_true (scm_procedure_p (b)))
-	    break;
-	  SCM_ASSERT (scm_is_pair (b), env, SCM_ARG2, FUNC_NAME);
-	  for (b = SCM_CAR (b); SCM_NIMP (b); b = SCM_CDR (b))
-	    {
-	      if (!scm_is_pair (b))
-		{
-		  if (scm_is_eq (b, sym))
-		    return SCM_BOOL_T;
-		  else
-		    break;
-		}
-	      if (scm_is_eq (SCM_CAR (b), sym))
-		return SCM_BOOL_T;
-	    }
-	}
-      var = scm_sym2var (sym,
-			 SCM_NIMP (frames) ? SCM_CAR (frames) : SCM_BOOL_F,
-			 SCM_BOOL_F);
-    }
-	      
+    SCM_VALIDATE_MODULE (2, module);
+
+  var = scm_module_variable (module, sym);
+
   return (scm_is_false (var) || SCM_UNBNDP (SCM_VARIABLE_REF (var))
 	  ? SCM_BOOL_F
 	  : SCM_BOOL_T);