1 files changed, 47 insertions, 0 deletions
diff --git a/JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java b/JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java
new file mode 100644
index 0000000..c608362
--- /dev/null
+++ b/JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java
@@ -0,0 +1,47 @@
+package bjc.utils.parserutils.pratt.commands;
+
+import bjc.utils.data.ITree;
+import bjc.utils.data.Tree;
+import bjc.utils.parserutils.ParserException;
+import bjc.utils.parserutils.pratt.ParserContext;
+import bjc.utils.parserutils.pratt.Token;
+
+/**
+ * A unary operator.
+ * 
+ * @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 UnaryCommand<K, V, C> extends AbstractInitialCommand<K, V, C> {
+	private final int nullPwer;
+
+	/**
+	 * Create a new unary command.
+	 * 
+	 * @param precedence
+	 *                The precedence of this operator.
+	 */
+	public UnaryCommand(int precedence) {
+		if(precedence < 0) {
+			throw new IllegalArgumentException("Precedence must be non-negative");
+		}
+		
+		nullPwer = precedence;
+	}
+
+	@Override
+	protected ITree<Token<K, V>> intNullDenotation(Token<K, V> operator, ParserContext<K, V, C> ctx)
+			throws ParserException {
+		ITree<Token<K, V>> opr = ctx.parse.parseExpression(nullPwer, ctx.tokens, ctx.state, false);
+
+		return new Tree<>(operator, opr);
+	}
+}
+\ No newline at end of file