# HG changeset patch
# User jwe
# Date 845491586 0
# Node ID 449f35baba4974036c99c62933529cfb28cdfae3
# Parent  015cbef2b75f29499bb5f3bad4b38bed7dbe1106
[project @ 1996-10-16 18:46:25 by jwe]

diff --git a/src/ChangeLog b/src/ChangeLog
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,13 @@
 Wed Oct 16 12:00:11 1996  John W. Eaton  <jwe@bevo.che.wisc.edu>
 
+	* ov.h (octave_value::struct_elt_val): New optional arg, silent.
+	* ov-base.h, ov-base.cc, ov-struct.h, ov-struct.cc: Likewise, but
+	for the derived classes the arg is required.
+
+	* data.cc (Fstruct_contains): Require arguments to be struct and
+	string, respectively.  Call octave_value::struct_elt_val with
+	silent flag set.
+
 	* pt-mat.cc (tm_row_const::tm_row_const_rep::eval_error,
 	tm_row_const::tm_row_const_rep::eval_warning): New functions.
 	(tm_row_const::tm_row_const (const tree_matrix_row&): Use them to
diff --git a/src/data.cc b/src/data.cc
--- a/src/data.cc
+++ b/src/data.cc
@@ -783,7 +783,8 @@
 DEFUN (struct_contains, args, ,
   "struct_contains (S, NAME)\n\
 \n\
-return nonzero if S is a structure with element NAME")
+Return nonzero if S is a structure with element NAME.\n\
+S must be a structure and NAME must be a string.")
 {
   octave_value_list retval;
 
@@ -792,12 +793,15 @@
   if (nargin == 2)
     {
       retval = 0.0;
+
       if (args(0).is_map () && args(1).is_string ())
 	{
 	  string s = args(1).string_value ();
-	  octave_value tmp = args(0).struct_elt_val (s);
+	  octave_value tmp = args(0).struct_elt_val (s, true);
 	  retval = (double) tmp.is_defined ();
 	}
+      else
+	print_usage ("struct_contains");
     }
   else
     print_usage ("struct_contains");
diff --git a/src/ov-base.cc b/src/ov-base.cc
--- a/src/ov-base.cc
+++ b/src/ov-base.cc
@@ -63,7 +63,7 @@
 }
 
 octave_value
-octave_base_value::struct_elt_val (const string&) const
+octave_base_value::struct_elt_val (const string&, bool) const
 {
   string nm = type_name ();
   error ("can't perform structure reference operations for %s type",
diff --git a/src/ov-base.h b/src/ov-base.h
--- a/src/ov-base.h
+++ b/src/ov-base.h
@@ -77,7 +77,7 @@
 
   idx_vector index_vector (void) const;
 
-  octave_value struct_elt_val (const string& nm) const;
+  octave_value struct_elt_val (const string& nm, bool silent) const;
 
   octave_value& struct_elt_ref (const string& nm);
 
diff --git a/src/ov-struct.cc b/src/ov-struct.cc
--- a/src/ov-struct.cc
+++ b/src/ov-struct.cc
@@ -40,7 +40,7 @@
 
 
 octave_value
-octave_struct::struct_elt_val (const string& nm) const
+octave_struct::struct_elt_val (const string& nm, bool silent) const
 {
   octave_value retval;
 
@@ -48,7 +48,7 @@
 
   if (idx)
     retval = map.contents (idx);
-  else
+  else if (! silent)
     error ("structure has no member `%s'", nm.c_str ());
 
   return retval;
diff --git a/src/ov-struct.h b/src/ov-struct.h
--- a/src/ov-struct.h
+++ b/src/ov-struct.h
@@ -71,7 +71,7 @@
   void operator delete (void *p, size_t size);
 #endif
 
-  octave_value struct_elt_val (const string& nm) const;
+  octave_value struct_elt_val (const string& nm, bool silent) const;
 
   octave_value& struct_elt_ref (const string& nm);
 
diff --git a/src/ov.h b/src/ov.h
--- a/src/ov.h
+++ b/src/ov.h
@@ -189,8 +189,9 @@
   virtual idx_vector index_vector (void) const
     { return rep->index_vector (); }
 
-  virtual octave_value struct_elt_val (const string& nm) const
-    { return rep->struct_elt_val (nm); }
+  virtual octave_value
+  struct_elt_val (const string& nm, bool silent = false) const
+    { return rep->struct_elt_val (nm, silent); }
 
   virtual octave_value& struct_elt_ref (const string& nm)
     { return rep->struct_elt_ref (nm); }