Revert "boost::none_t no longer convertible from literal 0 in 1.58"

This reverts commit 48aec0f093ff6494a3e4f7cd5166cb4a27c16814.

5 files changed, 21 insertions, 5 deletions

diff --git a/src/account.h b/src/account.h
index 8d0fb1db..7fae93e1 100644
--- a/src/account.h
+++ b/src/account.h
@@ -261,7 +261,11 @@ public:
   mutable optional<xdata_t> xdata_;
 
   bool has_xdata() const {
-    return xdata_ != boost::none;
+#if BOOST_VERSION >= 105600
+    return xdata_ != NULL;
+#else
+    return xdata_;
+#endif
   }
   void clear_xdata();
   xdata_t& xdata() {
diff --git a/src/item.h b/src/item.h
index 2c349bdc..ba812175 100644
--- a/src/item.h
+++ b/src/item.h
@@ -174,7 +174,11 @@ public:
   static bool use_aux_date;
 
   virtual bool has_date() const {
-    return _date != boost::none;
+#if BOOST_VERSION >= 105600
+    return _date != NULL;
+#else
+    return _date;
+#endif
   }
 
   virtual date_t date() const {
diff --git a/src/parser.h b/src/parser.h
index 25c4a7e3..e46fc719 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -118,7 +118,7 @@ public:
 
   ptr_op_t parse(std::istream&           in,
                  const parse_flags_t&    flags           = PARSE_DEFAULT,
-                 const optional<string>& original_string = boost::none);
+                 const optional<string>& original_string = NULL);
 };
 
 } // namespace ledger
diff --git a/src/post.h b/src/post.h
index 3fa67e56..0fb45e90 100644
--- a/src/post.h
+++ b/src/post.h
@@ -205,7 +205,11 @@ public:
   mutable optional<xdata_t> xdata_;
 
   bool has_xdata() const {
-    return xdata_ != boost::none;
+#if BOOST_VERSION >= 105600
+    return xdata_ != NULL;
+#else
+    return xdata_;
+#endif
   }
   void clear_xdata() {
     xdata_ = none;
diff --git a/src/times.h b/src/times.h
index cc980858..421d1462 100644
--- a/src/times.h
+++ b/src/times.h
@@ -500,7 +500,11 @@ public:
   void   stabilize(const optional<date_t>& date = none);
 
   bool   is_valid() const {
-    return start != boost::none;
+#if BOOST_VERSION >= 105600
+    return start != NULL;
+#else
+    return start;
+#endif
   }
 
   /** Find the current or next period containing date.  Returns false if