antlr4: Fixed the support for reference values

Author: hexaredecimal

src/main/antlr4/PiccodeScript.g4

@@ -101,7 +101,8 @@ unary:
 	| SUB expr
 	| RETURN_TOK expr
 	| TILDE expr
-	| BAND expr;
+	| BAND expr
+	| MUL expr;
 
 if_expr:
 	IF expr expr (ELSE expr)?;

src/main/java/org/piccode/rt/PiccodeReference.java

@@ -0,0 +1,54 @@
+
+package org.piccode.rt;
+
+import java.util.Objects;
+
+/**
+ *
+ * @author hexaredecimal
+ */
+public class PiccodeString implements PiccodeValue {
+	public static final Type TYPE = Type.STRING;
+	private String string;
+
+	public PiccodeString(String str) {
+		this.string = str;
+	}
+	
+	@Override
+	public Object raw() {
+		return string;
+	}
+
+	@Override
+	public String toString() {
+		return string;
+	}
+
+	@Override
+	public int hashCode() {
+		int hash = 5;
+		hash = 47 * hash + Objects.hashCode(this.string);
+		return hash;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj) {
+			return true;
+		}
+		if (obj == null) {
+			return false;
+		}
+		if (getClass() != obj.getClass()) {
+			return false;
+		}
+		final PiccodeString other = (PiccodeString) obj;
+		return Objects.equals(this.string, other.string);
+	}
+
+	@Override
+	public String type() {
+		return "String";
+	}
+}

src/main/java/org/piccode/rt/modules/PiccodeRefModule.java

@@ -0,0 +1,48 @@
+package org.piccode.rt.modules;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import org.piccode.rt.Context;
+import org.piccode.rt.PiccodeArray;
+import org.piccode.rt.PiccodeNumber;
+import org.piccode.rt.PiccodeTuple;
+import org.piccode.rt.PiccodeValue;
+import org.piccode.rt.PiccodeValue.Type;
+
+
+/**
+ *
+ * @author hexaredecimal
+ */
+public class PiccodeTupleModule {
+	public static void addFunctions() {
+		
+		NativeFunctionFactory.create("tuplesize", List.of("tuple"), (args, namedArgs, frame) -> {
+				var ctx = frame == null ? 
+						Context.top
+						: Context.getContextAt(frame);
+				var caller = ctx.getTopFrame().caller;
+				
+				var tup = namedArgs.get("tuple");
+				PiccodeValue.verifyType(caller, tup, Type.TYPLE);
+				var arr = ((PiccodeTuple) tup).array().length;
+				return new PiccodeNumber("" + arr);
+		}, null);
+		
+		NativeFunctionFactory.create("tupletoarray", List.of("tuple"), (args, namedArgs, frame) -> {
+				var ctx = frame == null ? 
+						Context.top
+						: Context.getContextAt(frame);
+				var caller = ctx.getTopFrame().caller;
+				
+				var tup = namedArgs.get("tuple");
+				PiccodeValue.verifyType(caller, tup, Type.TYPLE);
+				var arr = ((PiccodeTuple) tup).array();
+				var list = new ArrayList<PiccodeValue>();
+				list.addAll(Arrays.asList(arr));
+				return new PiccodeArray(list);
+		}, null);
+		
+	}
+}