From 4e3db7fefd9fe058fdf759d5c41cce6c286a7d4d Mon Sep 17 00:00:00 2001
From: Chris Hanson <org/chris-hanson/cph>
Date: Mon, 13 Aug 2007 17:17:47 +0000
Subject: [PATCH] Add predicates and guarantees to validate components of a
 triple.

---
 v7/src/xml/rdf-struct.scm | 20 +++++++++++++++++++-
 v7/src/xml/xml.pkg        | 11 ++++++++++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/v7/src/xml/rdf-struct.scm b/v7/src/xml/rdf-struct.scm
index bb221d946..39f78e7b8 100644
--- a/v7/src/xml/rdf-struct.scm
+++ b/v7/src/xml/rdf-struct.scm
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Id: rdf-struct.scm,v 1.31 2007/08/10 19:26:02 cph Exp $
+$Id: rdf-struct.scm,v 1.32 2007/08/13 17:17:45 cph Exp $
 
 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
     1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
@@ -69,6 +69,24 @@ USA.
 (define rdf-triples (make-equal-hash-table))
 (define event:new-rdf-triple (make-event-distributor))
 
+(define (rdf-subject? thing)
+  (or (absolute-uri? thing)
+      (rdf-bnode? thing)
+      (rdf-graph? thing)))
+
+(define (rdf-predicate? thing)
+  (absolute-uri? thing))
+
+(define (rdf-object? thing)
+  (or (absolute-uri? thing)
+      (rdf-bnode? thing)
+      (rdf-graph? thing)
+      (rdf-literal? thing)))
+
+(define-guarantee rdf-subject "RDF subject")
+(define-guarantee rdf-predicate "RDF predicate")
+(define-guarantee rdf-object "RDF object")
+
 (define (canonicalize-rdf-subject subject #!optional caller)
   (cond ((or (rdf-bnode? subject) (rdf-graph? subject)) subject)
 	((%decode-bnode-uri subject))
diff --git a/v7/src/xml/xml.pkg b/v7/src/xml/xml.pkg
index 96755aeef..8cd300347 100644
--- a/v7/src/xml/xml.pkg
+++ b/v7/src/xml/xml.pkg
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Id: xml.pkg,v 1.97 2007/08/10 19:26:03 cph Exp $
+$Id: xml.pkg,v 1.98 2007/08/13 17:17:47 cph Exp $
 
 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
     1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
@@ -548,9 +548,12 @@ USA.
 	  error:not-rdf-bnode
 	  error:not-rdf-graph
 	  error:not-rdf-literal
+	  error:not-rdf-object
+	  error:not-rdf-predicate
 	  error:not-rdf-prefix
 	  error:not-rdf-prefix-registry
 	  error:not-rdf-qname
+	  error:not-rdf-subject
 	  error:not-rdf-triple
 	  event:new-rdf-graph
 	  event:new-rdf-triple
@@ -558,9 +561,12 @@ USA.
 	  guarantee-rdf-bnode
 	  guarantee-rdf-graph
 	  guarantee-rdf-literal
+	  guarantee-rdf-object
+	  guarantee-rdf-predicate
 	  guarantee-rdf-prefix
 	  guarantee-rdf-prefix-registry
 	  guarantee-rdf-qname
+	  guarantee-rdf-subject
 	  guarantee-rdf-triple
 	  make-rdf-bnode
 	  make-rdf-graph
@@ -579,6 +585,8 @@ USA.
 	  rdf-literal-text
 	  rdf-literal-type
 	  rdf-literal?
+	  rdf-object?
+	  rdf-predicate?
 	  rdf-prefix-expansion
 	  rdf-prefix-registry->alist
 	  rdf-prefix-registry?
@@ -587,6 +595,7 @@ USA.
 	  rdf-qname-local
 	  rdf-qname-prefix
 	  rdf-qname?
+	  rdf-subject?
 	  rdf-triple-object
 	  rdf-triple-predicate
 	  rdf-triple-subject
-- 
2.25.1