Getters and setters for bytes in a QByteArray from scripts

src/typica.w

 QScriptValue constructQByteArray(QScriptContext *context, QScriptEngine *engine);
 void setQByteArrayProperties(QScriptValue value, QScriptEngine *engine);
 QScriptValue QByteArray_fromHex(QScriptContext *context, QScriptEngine *engine);
+QScriptValue QByteArray_getAt(QScriptContext *context, QScriptEngine *engine);
+QScriptValue QByteArray_setAt(QScriptContext *context, QScriptEngine *engine);
 
 @ First, we provide some functionns for moving array data across the
 language barrier.
 void setQByteArrayProperties(QScriptValue value, QScriptEngine *engine)
 {
 	value.setProperty("fromHex", engine->newFunction(QByteArray_fromHex));
+	value.setProperty("getAt", engine->newFunction(QByteArray_getAt));
+	value.setProperty("setAt", engine->newFunction(QByteArray_setAt));
 }
 
 @ Perhaps the easiest way to deal with fixed byte strings for serial
 	return engine->toScriptValue<QByteArray>(retval);
 }
 
+@ A pair of methods is provided for getting and setting values at a particular
+byte.
+
+@<Functions for scripting@>=
+QScriptValue QByteArray_getAt(QScriptContext *context, QScriptEngine *)
+{
+	QByteArray self = getself<QByteArray>(context);
+	return QScriptValue((int)(self.at(argument<int>(0, context))));
+}
+
+QScriptValue QByteArray_setAt(QScriptContext *context, QScriptEngine *)
+{
+	QByteArray self = getself<QByteArray>(context);
+	self[argument<int>(0, context)] = (char)(argument<int>(1, context));
+}
+
 @* Scripting QBuffer.
 
 \noindent Sometimes it is desirable to load a roast profile from a file. At