Adapted FunctionBase template to accept multiple argument types

* FunctionBase::argument_tuple is a std::tuple specialization type specialized on the argument types passed inside the variadic template argument of FunctionBase
* added tuple Mapper and XObjectValue helper namespaces containing recursive tuple construction and XObjectPtr value extraction logic
* changed all external function implementations accordingly
* this change was implemented to uniformly support different external function argument types than std::string

1 files changed, 18 insertions, 0 deletions

diff --git a/src/support/tuple/xobject_value.cc b/src/support/tuple/xobject_value.cc
new file mode 100644
index 0000000..3883436
--- /dev/null
+++ b/src/support/tuple/xobject_value.cc
@@ -0,0 +1,18 @@
+#include "xobject_value.h"
+
+#include <string>
+
+#include "support/xalan_string.h"
+
+namespace InputXSLT {
+
+namespace XObjectValue {
+
+template <>
+std::string get<std::string>(const xalan::XObjectPtr& ptr) {
+	return toString(ptr->str());
+}
+
+}
+
+}