From: crawshaw <crawshaw@ibex.org>
Date: Thu, 25 Nov 2004 11:26:28 +0000 (+0000)
Subject: introduce global attribute processing
X-Git-Url: http://git.megacz.com/?p=org.ibex.xt-crawshaw.git;a=commitdiff_plain;h=628fd95c0956c0ef41189f9dcb42677c2daca320

introduce global attribute processing

darcs-hash:20041125112628-2eb37-0d69a629f49f5992fc590f84045c6126c80543d0.gz
---

diff --git a/src/java/org/ibex/xt/JSElement.java b/src/java/org/ibex/xt/JSElement.java
index c6eee6e..35ee51e 100644
--- a/src/java/org/ibex/xt/JSElement.java
+++ b/src/java/org/ibex/xt/JSElement.java
@@ -32,21 +32,7 @@ public class JSElement extends JSScope implements XML.Element {
     public void out(OutputStream o) throws IOException { wrapped.out(o); }
     public void out(Writer w) throws IOException { wrapped.out(w); }
 
-    /** Load the attributes into the js scope. */
-    protected void loadAttr() {
-        try {
-            XML.Attributes a = getAttributes();
-            // FIXME: questionable abuse of XML namespaces here
-            boolean xturi = "http://xt.ibex.org/".equals(getUri());
-            for(int i=0; i < a.attrSize(); i++) {
-                if (!xturi && !"http://xt.ibex.org/".equals(a.getUri(i))) continue;
-                declare(a.getKey(i));
-                put(a.getKey(i), eval(a.getVal(i)));
-            }
-        } catch (JSExn e) { throw new Exn(e); }
-    }
-
-    private Object eval(String s) {
+    protected Object eval(String s) {
         if (s == null) return null;
         StringBuffer ret = new StringBuffer();
         while (s.indexOf("${") != -1) {
@@ -75,7 +61,7 @@ public class JSElement extends JSScope implements XML.Element {
                            JS.fromReader("input", 0, new StringReader(s)), this));
         } catch (IOException e) {
             e.printStackTrace();
-            throw new Exn("impossible IOException, reading from StringReader");
+            throw new Exn("error parsing script", e);
         } catch (JSExn e) {
             throw new Exn(e);
         }
@@ -154,6 +140,7 @@ public class JSElement extends JSScope implements XML.Element {
     public static class Exn extends RuntimeException {
         public Exn(String cause) { super(cause); }
         public Exn(JSExn e) { super(e); }
+        public Exn(String msg, Exception e) { super(msg + ": " + e.getMessage()); }
         public String toString() { return "JSElement.Exn: "+getMessage(); }
     }
 }
diff --git a/src/java/org/ibex/xt/Template.java b/src/java/org/ibex/xt/Template.java
index 4ab16d6..7f75bd2 100644
--- a/src/java/org/ibex/xt/Template.java
+++ b/src/java/org/ibex/xt/Template.java
@@ -25,7 +25,9 @@ public class Template extends JSElement {
     public static XML.Element wrap(XML.Element e, Template.Scope s) throws IOException {
         final String uri = e.getUri();
 
-        if (uri.equals("http://xt.ibex.org/")) {
+        if (uri == null) {
+            // do nothing
+        } else if (uri.equals("http://xt.ibex.org/")) {
             //#switch(e.getLocalName())
             case "js":          e = new Template.JSTag(e); break;
             case "foreach":     e = new Template.ForEach(e); break;
@@ -68,15 +70,7 @@ public class Template extends JSElement {
             return wrap(merged, s);
         }
 
-        XML.Attributes a = e.getAttributes();
-        for (int i=0; i < a.attrSize(); i++) {
-            // FIXME: questionable abuse of XML namespaces here
-            if ("if".equals(a.getKey(i)) && (
-                "http://xt.ibex.org/".equals(e.getUri()) ||
-                "http://xt.ibex.org/".equals(a.getUri(i)))) {
-                e = new Template.IfWrap(e);
-            }
-        }
+        e = new Template.AttributeEval(e);
 
         // wrap children
         List c = e.getChildren();
@@ -106,16 +100,48 @@ public class Template extends JSElement {
 
     public JSScope getParentScope() { return tscope; }
 
-    public static final class IfWrap extends JSElement {
-        public IfWrap(XML.Element e) { super(e); }
 
-        public void out(Writer w) throws IOException {
-            loadAttr();
+    /** Processes ${...} blocks in attributes, loads applicable
+     *  attributes into the JS scope and processes global attributes. */
+    public static class AttributeEval extends JSElement implements XML.Attributes {
+        protected XML.Attributes a;
+
+        public AttributeEval(XML.Element wrapped) { super(wrapped); a = wrapped.getAttributes(); }
 
+        public XML.Attributes getAttributes() { return this; }
+
+        public int getIndex(String q) { return a.getIndex(q); }
+        public int getIndex(String u, String k) { return a.getIndex(u, k); }
+        public String getKey(int i) { return a.getKey(i); }
+        public String getVal(int i) { return (String)eval(a.getVal(i)); }
+        public String getUri(int i) { return a.getUri(i); }
+        public String getPrefix(int i) { return a.getPrefix(i); }
+        public String getQName(int i) { return a.getQName(i); }
+        public int attrSize() { return a.attrSize(); }
+
+        public void out(Writer w) throws IOException {
             try {
-                Object varIf = get("if"); if (varIf != null) undeclare("if");
-                if (varIf != null && !"true".equals(varIf)) return;
-            } catch (JSExn e) { throw new JSElement.Exn(e); }
+                // FIXME: questionable abuse of XML namespaces here
+                boolean xturi = "http://xt.ibex.org/".equals(getUri());
+                for(int i=0; i < a.attrSize(); i++) {
+                    if (!xturi && !"http://xt.ibex.org/".equals(a.getUri(i))) continue;
+
+                    //#switch (a.getKey(i))
+                    case "if": if (!"true".equals(eval(a.getVal(i)))) return;
+                    case "declare":
+                        Object d = eval(a.getVal(i));
+                        if (!(d instanceof String)) throw new JSElement.Exn(
+                            "attribute "+getPrefix()+":declare can only contain a "+
+                            "space seperated list of variable names to declare.");
+                        StringTokenizer st = new StringTokenizer((String)d, " ");
+                        while (st.hasMoreTokens()) declare(st.nextToken());
+                        continue;
+                    //#end
+
+                    declare(a.getKey(i));
+                    put(a.getKey(i), eval(a.getVal(i)));
+                }
+            } catch (JSExn e) { throw new Exn(e); }
 
             wrapped.out(w);
         }
@@ -131,8 +157,6 @@ public class Template extends JSElement {
         }
 
         public void out(Writer w) throws IOException {
-            loadAttr();
-
             List c = getChildren();
             StringWriter s = new StringWriter();
             for (int i=0; i < c.size(); i++) ((Tree.Leaf)c.get(i)).out(s);
@@ -144,8 +168,6 @@ public class Template extends JSElement {
         public ForEach(XML.Element e) { super(e); }
 
         public void out(Writer w) throws IOException {
-            loadAttr();
-
             try {
                 Object varIn = get("in"); if (varIn != null) undeclare("in");
                 Object varPut = get("put"); if (varPut != null) undeclare("put");
@@ -183,8 +205,6 @@ public class Template extends JSElement {
         public Redirect(XML.Element e) { super(e); }
 
         public void out(Writer w) throws IOException {
-            loadAttr();
-
             try {
                 Object p = get("page"); if (p != null) undeclare("page");
                 if (p == null || !(p instanceof String) || ((String)p).trim().equals(""))
@@ -201,8 +221,6 @@ public class Template extends JSElement {
         public Transaction(XML.Element e, Template.Scope s) { super(e); scope = s;} // TODO: check kids
 
         public void out(Writer w) throws IOException {
-            loadAttr();
-
             // TODO: <xt:use />
             List c = getChildren();
             StringWriter sw = new StringWriter();