1 files changed, 108 insertions, 0 deletions
diff --git a/tool/src/org/antlr/v4/tool/AttributeDict.java b/tool/src/org/antlr/v4/tool/AttributeDict.java
new file mode 100644
index 0000000..911170d
--- /dev/null
+++ b/tool/src/org/antlr/v4/tool/AttributeDict.java
@@ -0,0 +1,108 @@
+/*
+ * [The "BSD license"]
+ *  Copyright (c) 2012 Terence Parr
+ *  Copyright (c) 2012 Sam Harwell
+ *  All rights reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions
+ *  are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.antlr.v4.tool;
+
+import org.antlr.v4.runtime.Token;
+import org.antlr.v4.tool.ast.GrammarAST;
+
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.Set;
+
+/** Track the attributes within retval, arg lists etc...
+ *  <p/>
+ *  Each rule has potentially 3 scopes: return values,
+ *  parameters, and an implicitly-named scope (i.e., a scope defined in a rule).
+ *  Implicitly-defined scopes are named after the rule; rules and scopes then
+ *  must live in the same name space--no collisions allowed.
+ */
+public class AttributeDict {
+    public String name;
+    public GrammarAST ast;
+	public DictType type;
+
+    /** All {@link Token} scopes (token labels) share the same fixed scope of
+     *  of predefined attributes.  I keep this out of the {@link Token}
+     *  interface to avoid a runtime type leakage.
+     */
+    public static final AttributeDict predefinedTokenDict = new AttributeDict(DictType.TOKEN);
+    static {
+        predefinedTokenDict.add(new Attribute("text"));
+        predefinedTokenDict.add(new Attribute("type"));
+        predefinedTokenDict.add(new Attribute("line"));
+        predefinedTokenDict.add(new Attribute("index"));
+        predefinedTokenDict.add(new Attribute("pos"));
+        predefinedTokenDict.add(new Attribute("channel"));
+        predefinedTokenDict.add(new Attribute("int"));
+    }
+
+    public static enum DictType {
+        ARG, RET, LOCAL, TOKEN,
+		PREDEFINED_RULE, PREDEFINED_LEXER_RULE,
+    }
+
+    /** The list of {@link Attribute} objects. */
+
+    public final LinkedHashMap<String, Attribute> attributes =
+        new LinkedHashMap<String, Attribute>();
+
+	public AttributeDict() {}
+	public AttributeDict(DictType type) { this.type = type; }
+
+	public Attribute add(Attribute a) { a.dict = this; return attributes.put(a.name, a); }
+    public Attribute get(String name) { return attributes.get(name); }
+
+    public String getName() {
+        return name;
+    }
+
+    public int size() { return attributes.size(); }
+
+    /** Return the set of keys that collide from
+     *  {@code this} and {@code other}.
+     */
+
+    public Set<String> intersection(AttributeDict other) {
+        if ( other==null || other.size()==0 || size()==0 ) {
+            return Collections.emptySet();
+        }
+
+		Set<String> result = new HashSet<String>(attributes.keySet());
+		result.retainAll(other.attributes.keySet());
+		return result;
+    }
+
+    @Override
+    public String toString() {
+        return getName()+":"+attributes;
+    }
+}