Copy some functionality of Ex to ExNode.

Author: Kasper Peeters

cmake/version.cmake

@@ -1,7 +1,7 @@
 set(CADABRA_VERSION_MAJOR 2)
 set(CADABRA_VERSION_MINOR 4)
 set(CADABRA_VERSION_PATCH 3)
-set(CADABRA_VERSION_TWEAK 4)
+set(CADABRA_VERSION_TWEAK 5)
 set(COPYRIGHT_YEARS "2001-2023")
 math(EXPR SYSTEM_BITS "${CMAKE_SIZEOF_VOID_P} * 8")
 find_program(GIT git PATHS ${GIT_DIR})

core/ExNode.cc

@@ -11,6 +11,7 @@
 #include "DisplayTeX.hh"
 #include "DisplaySympy.hh"
 #include "DisplayTerminal.hh"
+#include "pythoncdb/py_ex.hh"
 #include <sstream>
 
 //#define DEBUG 1
@@ -51,6 +52,17 @@ ExNode ExNode::copy() const
 	return ret;
 	}
 
+std::string ExNode::input_form() const
+   {
+		// FIXME: this is a duplicate of Ex_as_string; unify the logic.
+		std::ostringstream str;
+
+		DisplayTerminal dt(*get_kernel_from_scope(), get_ex(), false);
+		dt.output(str);
+
+		return str.str();
+   }
+
 ExNode ExNode::getitem_string(std::string tag)
 	{
 	ExNode ret(kernel, ex);

core/ExNode.hh

@@ -40,7 +40,8 @@ class ExNode : public cadabra::IndexClassifier {
 
 		std::string __str__() const;
 		std::string _latex_() const;
-
+	   std::string input_form() const;
+	
 		std::string get_name() const;
 		void        set_name(std::string);
 

core/cadabra2_defaults.py.in

@@ -269,6 +269,19 @@ def display(obj, delay_send=False):
         else:
             server.send(unicode(obj), "plain", 0, False)
 
+    elif isinstance(obj, ExNode):
+        if server.handles('latex_view'):
+            if delay_send:
+                return obj._latex_()
+            else:
+                ret = mopen+obj._latex_()+mclose
+                id=server.send(ret, "latex_view", 0, False)
+                # print(id)
+                # Make a child cell of the above with input form content.
+                server.send(obj.input_form(), "input_form", id, False)                
+        else:
+            server.send(unicode(obj), "plain", 0, False)
+
     elif isinstance(obj, Property):
         if server.handles('latex_view'):
             ret = mopen+obj._latex_()+mclose

core/pythoncdb/py_ex.cc

@@ -653,6 +653,7 @@ namespace cadabra {
 		pybind11::class_<ExNode>(m, "ExNode", "Iterator over elements of an Ex mathematical expression.")
 			.def("__iter__", &ExNode::iter)
 			.def("__next__", &ExNode::next, pybind11::return_value_policy::reference_internal)
+			.def("input_form",  &ExNode::input_form)
 			.def("__getitem__", &ExNode::getitem_string)
 			.def("__getitem__", &ExNode::getitem_iterator)
 			.def("__setitem__", &ExNode::setitem_string)