Added filter compacting

Before statement compilation, empty filters are removed from group
filters, and childless group filters become empty filters.

1 files changed, 42 insertions, 40 deletions

@@ -8,7 +8,7 @@
 #include "enums.h"
 
 namespace verbly {
-  
+
   class filter {
   public:
     enum class type {
@@ -16,7 +16,7 @@ namespace verbly {
       singleton,
       group
     };
-    
+
     enum class comparison {
       int_equals,
       int_does_not_equal,
@@ -36,87 +36,89 @@ namespace verbly {
       hierarchally_matches,
       does_not_hierarchally_match
     };
-    
+
     // Copy and move constructors
-    
+
     filter(const filter& other);
     filter(filter&& other);
-    
+
     // Assignment
-    
+
     filter& operator=(filter other);
-    
+
     // Swap
-    
+
     friend void swap(filter& first, filter& second);
-    
+
     // Destructor
-    
+
     ~filter();
-    
+
     // Accessors
-    
+
     type getType() const
     {
       return type_;
     }
-    
+
     // Empty
-    
+
     filter();
-    
+
     // Singleton
-    
+
     filter(field filterField, comparison filterType, int filterValue);
     filter(field filterField, comparison filterType, std::string filterValue);
     filter(field filterField, comparison filterType, bool filterValue);
     filter(field filterField, comparison filterType);
     filter(field joinOn, comparison filterType, filter joinCondition);
-    
+
     field getField() const;
-    
+
     comparison getComparison() const;
-    
+
     filter getJoinCondition() const;
-    
+
     std::string getStringArgument() const;
-    
+
     int getIntegerArgument() const;
-    
+
     bool getBooleanArgument() const;
-    
+
     // Group
-    
+
     explicit filter(bool orlogic);
-    
+
     bool getOrlogic() const;
-    
+
     filter operator+(filter condition) const;
-    
+
     filter& operator+=(filter condition);
-    
+
     using const_iterator = std::list<filter>::const_iterator;
-    
+
     const_iterator begin() const;
-    
+
     const_iterator end() const;
-    
+
     // Negation
-    
+
     filter operator!() const;
-    
+
     // Groupifying
-    
+
     filter operator&&(filter condition) const;
     filter operator||(filter condition) const;
-    
+
     filter& operator&=(filter condition);
     filter& operator|=(filter condition);
-    
+
     // Utility
-    
+
     filter normalize(object context) const;
-    
+
+    filter compact() const;
+
   private:
     union {
       struct {
@@ -135,9 +137,9 @@ namespace verbly {
       } group_;
     };
     type type_ = type::empty;
-    
+
   };
-  
+
 };
 
 #endif /* end of include guard: FILTER_H_932BA9C6 */