1 files changed, 38 insertions, 0 deletions
diff --git a/container-search/src/main/java/com/yahoo/search/yql/ParserBase.java b/container-search/src/main/java/com/yahoo/search/yql/ParserBase.java
new file mode 100644
index 00000000000..af3418919e8
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+++ b/container-search/src/main/java/com/yahoo/search/yql/ParserBase.java
@@ -0,0 +1,38 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.yql;
+
+import com.google.common.collect.Sets;
+
+import org.antlr.v4.runtime.Parser;
+import org.antlr.v4.runtime.TokenStream;
+import org.antlr.v4.runtime.tree.ParseTree;
+
+import java.util.Set;
+
+/**
+ * Provides semantic helper functions to Parser.
+ */
+abstract class ParserBase extends Parser {
+
+    private static String arrayRuleName = "array";
+    public ParserBase(TokenStream input) {
+        super(input);
+    }
+    
+    private Set<String> arrayParameters = Sets.newHashSet();
+
+    public void registerParameter(String name, String typeName) {
+        if (typeName.equals(arrayRuleName)) {
+            arrayParameters.add(name);
+       }
+    }
+
+    public boolean isArrayParameter(ParseTree nameNode) {
+        String name = nameNode.getText();
+        if (name.startsWith("@")) {
+            name = name.substring(1);
+        }
+        return name != null && arrayParameters.contains(name);
+    }
+
+}