1 files changed, 52 insertions, 0 deletions
diff --git a/JPratt/src/main/java/bjc/pratt/commands/TransformingInitialCommand.java b/JPratt/src/main/java/bjc/pratt/commands/TransformingInitialCommand.java
new file mode 100644
index 0000000..9ec3631
--- /dev/null
+++ b/JPratt/src/main/java/bjc/pratt/commands/TransformingInitialCommand.java
@@ -0,0 +1,52 @@
+package bjc.pratt.commands;
+
+import java.util.function.UnaryOperator;
+
+import bjc.pratt.InitialCommand;
+import bjc.pratt.ParserContext;
+import bjc.pratt.Token;
+import bjc.utils.data.ITree;
+import bjc.utils.parserutils.ParserException;
+
+/**
+ * An initial command that transforms the result of another command.
+ * 
+ * @author bjculkin
+ *
+ * @param <K>
+ *                The key type of the tokens.
+ * 
+ * @param <V>
+ *                The value type of the tokens.
+ * 
+ * @param <C>
+ *                The state type of the parser.
+ */
+public class TransformingInitialCommand<K, V, C> extends AbstractInitialCommand<K, V, C> {
+	private InitialCommand<K, V, C> internal;
+
+	private UnaryOperator<ITree<Token<K, V>>> transform;
+
+	/**
+	 * Create a new transforming initial command.
+	 * 
+	 * @param internal
+	 *                The initial command to delegate to.
+	 * 
+	 * @param transform
+	 *                The transform to apply to the returned tree.
+	 */
+	public TransformingInitialCommand(InitialCommand<K, V, C> internal,
+			UnaryOperator<ITree<Token<K, V>>> transform) {
+		super();
+		this.internal = internal;
+		this.transform = transform;
+	}
+
+	@Override
+	protected ITree<Token<K, V>> intNullDenotation(Token<K, V> operator, ParserContext<K, V, C> ctx)
+			throws ParserException {
+		return transform.apply(internal.denote(operator, ctx));
+	}
+
+}