Allow expr_t& to be passed in a value_t

src/value.cc

@@ -36,6 +36,7 @@
 #include "annotate.h"
 #include "pool.h"
 #include "unistring.h"		// for justify()
+#include "op.h"
 
 namespace ledger {
 
@@ -115,6 +116,8 @@ value_t::operator bool() const
     return false;
   case SCOPE:
     return as_scope() != NULL;
+  case EXPR:
+    return as_expr();
   default:
     break;
   }
@@ -140,6 +143,12 @@ void value_t::set_type(type_t new_type)
   }
 }
 
+void value_t::set_expr(const expr_t& val)
+{
+  set_type(EXPR);
+  storage->data = new expr_t(val);
+}
+
 bool value_t::to_boolean() const
 {
   if (is_boolean()) {
@@ -1272,6 +1281,8 @@ bool value_t::is_realzero() const
 
   case SCOPE:
     return as_scope() == NULL;
+  case EXPR:
+    return ! as_expr();
 
   default:
     throw_(value_error, _("Cannot determine if %1 is really zero") << label());
@@ -1301,6 +1312,8 @@ bool value_t::is_zero() const
 
   case SCOPE:
     return as_scope() == NULL;
+  case EXPR:
+    return ! as_expr();
 
   default:
     throw_(value_error, _("Cannot determine if %1 is zero") << label());
@@ -1565,6 +1578,7 @@ value_t value_t::strip_annotations(const keep_details_t& what_to_keep) const
   case STRING:
   case MASK:
   case SCOPE:
+  case EXPR:
     return *this;
 
   case SEQUENCE: {
@@ -1673,7 +1687,15 @@ void value_t::print(std::ostream& out,
   }
 
   case SCOPE:
-    out << "<SCOPE>";
+    out << "<#SCOPE>";
+    break;
+  case EXPR:
+    out << "<#EXPR ";
+    if (as_expr())
+      as_expr().print(out);
+    else
+      out << "null";
+    out << ">";
     break;
 
   default:
@@ -1743,6 +1765,12 @@ void value_t::dump(std::ostream& out, const bool relaxed) const
   case SCOPE:
     out << as_scope();
     break;
+  case EXPR:
+    if (as_expr())
+      as_expr().dump(out);
+    else
+      out << "null";
+    break;
 
   case SEQUENCE: {
     out << '(';
@@ -1855,6 +1883,7 @@ void to_xml(std::ostream& out, const value_t& value)
   }
 
   case value_t::SCOPE:
+  case value_t::EXPR:
   default:
     assert(false);
     break;

src/value.h

@@ -57,6 +57,7 @@ namespace ledger {
 DECLARE_EXCEPTION(value_error, std::runtime_error);
 
 class scope_t;
+class expr_t;
 
 /**
  * @class value_t
@@ -108,7 +109,8 @@ public:
     STRING,			// a string object
     MASK,			// a regular expression mask
     SEQUENCE,			// a vector of value_t objects
-    SCOPE			// a pointer to a scope
+    SCOPE,			// a pointer to a scope
+    EXPR			// a pointer to a value expression
   };
 
 private:
@@ -135,7 +137,8 @@ private:
 	    string,	  // STRING
 	    mask_t,	  // MASK
 	    sequence_t *, // SEQUENCE
-	    scope_t *	  // SCOPE
+	    scope_t *,	  // SCOPE
+	    expr_t *	  // EXPR
 	    > data;
     
     type_t type;
@@ -351,6 +354,10 @@ public:
     TRACE_CTOR(value_t, "scope_t *");
     set_scope(item);
   }
+  explicit value_t(const expr_t& item) {
+    TRACE_CTOR(value_t, "const expr_t&");
+    set_expr(item);
+  }
 
   /**
    * Destructor.  This does not do anything, because the intrusive_ptr
@@ -722,6 +729,22 @@ public:
     storage->data = val;
   }
 
+  /**
+   * Dealing with expr pointers.
+   */
+  bool is_expr() const {
+    return is_type(EXPR);
+  }
+  expr_t& as_expr_lval() const {
+    VERIFY(is_expr());
+    return *boost::get<expr_t *>(storage->data);
+  }
+  const expr_t& as_expr() const {
+    VERIFY(is_expr());
+    return *boost::get<expr_t *>(storage->data);
+  }
+  void set_expr(const expr_t& val);
+
   /**
    * Data conversion methods.  These methods convert a value object to
    * its underlying type, where possible.  If not possible, an
@@ -908,6 +931,8 @@ public:
       return _("a sequence");
     case SCOPE:
       return _("a scope");
+    case EXPR:
+      return _("a expr");
     default:
       assert(false);
       break;