From ff4589caae7b5bd40350eac605916d085b5106cc Mon Sep 17 00:00:00 2001
From: John Wiegley <johnw@newartisans.com>
Date: Fri, 10 Sep 2004 20:08:07 -0400
Subject: [PATCH] added support for ValueExpr objects to python.

---
 format.cc   | 11 ++++++++---
 format.h    |  2 +-
 main.py     | 11 +++++++----
 pyledger.cc |  2 ++
 valexpr.cc  | 32 ++++++++++++++++++++++++++++++++
 5 files changed, 50 insertions(+), 8 deletions(-)

diff --git a/format.cc b/format.cc
index 0f39b423..36b0bd16 100644
--- a/format.cc
+++ b/format.cc
@@ -14,11 +14,11 @@ std::string truncated(const std::string& str, unsigned int width)
   return buf;
 }
 
-std::string partial_account_name(const account_t *  account)
+std::string partial_account_name(const account_t&  account)
 {
   std::string name;
 
-  for (const account_t * acct = account;
+  for (const account_t * acct = &account;
        acct && acct->parent;
        acct = acct->parent) {
     if (acct->data && ACCT_DATA(acct)->dflags & ACCOUNT_DISPLAYED)
@@ -284,7 +284,7 @@ void format_t::format(std::ostream& out, const details_t& details) const
       if (details.account) {
 	std::string name = (elem->type == element_t::ACCOUNT_FULLNAME ?
 			    details.account->fullname() :
-			    partial_account_name(details.account));
+			    partial_account_name(*details.account));
 
 	if (details.xact && details.xact->flags & TRANSACTION_VIRTUAL) {
 	  if (elem->max_width > 2)
@@ -454,6 +454,11 @@ void export_format()
     .def("format", py_format<entry_t>)
     .def("format", py_format<transaction_t>)
     ;
+
+  def("truncated", truncated);
+#if 0
+  def("partial_account_name", partial_account_name);
+#endif
 }
 
 #endif // USE_BOOST_PYTHON
diff --git a/format.h b/format.h
index 1e959931..df5dc49a 100644
--- a/format.h
+++ b/format.h
@@ -9,7 +9,7 @@ namespace ledger {
 
 std::string truncated(const std::string& str, unsigned int width);
 
-std::string partial_account_name(const account_t *  account,
+std::string partial_account_name(const account_t&   account,
 				 const unsigned int start_depth);
 
 struct element_t
diff --git a/main.py b/main.py
index 1e25b7ed..cad0e6e8 100644
--- a/main.py
+++ b/main.py
@@ -20,16 +20,19 @@ register_parser (parser)
 journal = Journal ()
 parse_journal_file (args[0], journal)
 
-class OutputTransaction (TransactionHandler):
-    def __init__ (self):
-	self.formatter = Format ("%D %-20P %N")
+class FormatTransaction (TransactionHandler):
+    def __init__ (self, fmt):
+	self.formatter = Format (fmt)
 	TransactionHandler.__init__ (self)
+
     def __call__ (self, xact):
 	print self.formatter.format(xact)
 
-handler = OutputTransaction()
+handler = FormatTransaction("%D %-20P %N")
 handler = FilterTransactions (handler, "/Checking/")
 
+expr = parse_value_expr ("a*2")
+
 for entry in journal:
     for xact in entry:
 	handler (xact)
diff --git a/pyledger.cc b/pyledger.cc
index 41910044..d0f2a4be 100644
--- a/pyledger.cc
+++ b/pyledger.cc
@@ -19,6 +19,7 @@ void export_gnucash();
 void export_option();
 void export_walk();
 void export_format();
+void export_valexpr();
 void export_datetime();
 
 BOOST_PYTHON_MODULE(ledger) {
@@ -36,5 +37,6 @@ BOOST_PYTHON_MODULE(ledger) {
   export_option();
   export_walk();
   export_format();
+  export_valexpr();
   export_datetime();
 }
diff --git a/valexpr.cc b/valexpr.cc
index 06f7dd09..f7763084 100644
--- a/valexpr.cc
+++ b/valexpr.cc
@@ -854,6 +854,38 @@ void dump_value_expr(std::ostream& out, const value_expr_t * node)
 
 } // namespace ledger
 
+#ifdef USE_BOOST_PYTHON
+
+#include <boost/python.hpp>
+
+using namespace boost::python;
+using namespace ledger;
+
+template <typename T>
+value_t py_compute(value_expr_t& value_expr, const T& item) {
+  value_t result;
+  value_expr.compute(result, details_t(item));
+  return result;
+}
+
+value_expr_t * py_parse_value_expr(const std::string& str) {
+  return parse_value_expr(str);
+}
+
+void export_valexpr()
+{
+  class_< value_expr_t > ("ValueExpr", init<value_expr_t::kind_t>())
+    .def("compute", py_compute<account_t>)
+    .def("compute", py_compute<entry_t>)
+    .def("compute", py_compute<transaction_t>)
+    ;
+
+  def("parse_value_expr", py_parse_value_expr,
+      return_value_policy<manage_new_object>());
+}
+
+#endif // USE_BOOST_PYTHON
+
 #ifdef TEST
 
 int main(int argc, char *argv[])