Started structural rewrite

The new object structure was designed to build on the existing WordNet
structure, while also adding in all of the data that we get from other sources.
More information about this can be found on the project wiki.

The generator has already been completely rewritten to generate a
datafile that uses the new structure. In addition, a number of indexes
are created, which does double the size of the datafile, but also allows
for much faster lookups. Finally, the new generator is written modularly
and is a lot more readable than the old one.

The verbly interface to the new object structure has mostly been
completed, but has not been tested fully. There is a completely new
search API which utilizes a lot of operator overloading; documentation
on how to use it should go up at some point.

Token processing and verb frames are currently unimplemented. Source for
these have been left in the repository for now.

1 files changed, 1365 insertions, 0 deletions

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+#include "filter.h"
+#include <stdexcept>
+#include <map>
+#include "notion.h"
+#include "word.h"
+#include "group.h"
+#include "frame.h"
+#include "lemma.h"
+#include "form.h"
+#include "pronunciation.h"
+
+namespace verbly {
+
+  filter::filter(const filter& other)
+  {
+    type_ = other.type_;
+    
+    switch (type_)
+    {
+      case type::empty:
+      {
+        break;
+      }
+      
+      case type::singleton:
+      {
+        new(&singleton_.filterField) field(other.singleton_.filterField);
+        singleton_.filterType = other.singleton_.filterType;
+        
+        switch (singleton_.filterType)
+        {
+          case comparison::int_equals:
+          case comparison::int_does_not_equal:
+          case comparison::int_is_at_least:
+          case comparison::int_is_greater_than:
+          case comparison::int_is_at_most:
+          case comparison::int_is_less_than:
+          {
+            singleton_.intValue = other.singleton_.intValue;
+            
+            break;
+          }
+          
+          case comparison::boolean_equals:
+          {
+            singleton_.boolValue = other.singleton_.boolValue;
+            
+            break;
+          }
+          
+          case comparison::string_equals:
+          case comparison::string_does_not_equal:
+          case comparison::string_is_like:
+          case comparison::string_is_not_like:
+          {
+            new(&singleton_.stringValue) std::string(other.singleton_.stringValue);
+            
+            break;
+          }
+          
+          case comparison::is_null:
+          case comparison::is_not_null:
+          {
+            break;
+          }
+          
+          case comparison::matches:
+          case comparison::does_not_match:
+          case comparison::hierarchally_matches:
+          case comparison::does_not_hierarchally_match:
+          {
+            new(&singleton_.join) std::unique_ptr<filter>(new filter(*other.singleton_.join));
+            
+            break;
+          }
+        }
+        
+        break;
+      }
+      
+      case type::group:
+      {
+        new(&group_.children) std::list<filter>(other.group_.children);
+        group_.orlogic = other.group_.orlogic;
+        
+        break;
+      }
+    }
+  }
+  
+  filter::filter(filter&& other) : filter()
+  {
+    swap(*this, other);
+  }
+  
+  filter& filter::operator=(filter other)
+  {
+    swap(*this, other);
+    
+    return *this;
+  }
+  
+  void swap(filter& first, filter& second)
+  {
+    using type = filter::type;
+    using comparison = filter::comparison;
+    
+    type tempType = first.type_;
+    field tempField;
+    comparison tempComparison;
+    std::unique_ptr<filter> tempJoin;
+    std::string tempStringValue;
+    int tempIntValue;
+    bool tempBoolValue;
+    std::list<filter> tempChildren;
+    bool tempOrlogic;
+    
+    switch (tempType)
+    {
+      case type::empty:
+      {
+        break;
+      }
+      
+      case type::singleton:
+      {
+        tempField = std::move(first.singleton_.filterField);
+        tempComparison = first.singleton_.filterType;
+        
+        switch (tempComparison)
+        {
+          case comparison::int_equals:
+          case comparison::int_does_not_equal:
+          case comparison::int_is_at_least:
+          case comparison::int_is_greater_than:
+          case comparison::int_is_at_most:
+          case comparison::int_is_less_than:
+          {
+            tempIntValue = first.singleton_.intValue;
+            
+            break;
+          }
+          
+          case comparison::boolean_equals:
+          {
+            tempBoolValue = first.singleton_.boolValue;
+            
+            break;
+          }
+          
+          case comparison::string_equals:
+          case comparison::string_does_not_equal:
+          case comparison::string_is_like:
+          case comparison::string_is_not_like:
+          {
+            tempStringValue = std::move(first.singleton_.stringValue);
+            
+            break;
+          }
+          
+          case comparison::is_null:
+          case comparison::is_not_null:
+          {
+            break;
+          }
+          
+          case comparison::matches:
+          case comparison::does_not_match:
+          case comparison::hierarchally_matches:
+          case comparison::does_not_hierarchally_match:
+          {
+            tempJoin = std::move(first.singleton_.join);
+            
+            break;
+          }
+        }
+        
+        break;
+      }
+      
+      case type::group:
+      {
+        tempChildren = std::move(first.group_.children);
+        tempOrlogic = first.group_.orlogic;
+        
+        break;
+      }
+    }
+    
+    first.~filter();
+    
+    first.type_ = second.type_;
+    
+    switch (first.type_)
+    {
+      case type::empty:
+      {
+        break;
+      }
+      
+      case type::singleton:
+      {
+        new(&first.singleton_.filterField) field(std::move(second.singleton_.filterField));
+        first.singleton_.filterType = second.singleton_.filterType;
+        
+        switch (first.singleton_.filterType)
+        {
+          case comparison::int_equals:
+          case comparison::int_does_not_equal:
+          case comparison::int_is_at_least:
+          case comparison::int_is_greater_than:
+          case comparison::int_is_at_most:
+          case comparison::int_is_less_than:
+          {
+            first.singleton_.intValue = second.singleton_.intValue;
+            
+            break;
+          }
+          
+          case comparison::boolean_equals:
+          {
+            first.singleton_.boolValue = second.singleton_.boolValue;
+            
+            break;
+          }
+          
+          case comparison::string_equals:
+          case comparison::string_does_not_equal:
+          case comparison::string_is_like:
+          case comparison::string_is_not_like:
+          {
+            new(&first.singleton_.stringValue) std::string(std::move(second.singleton_.stringValue));
+            
+            break;
+          }
+          
+          case comparison::is_null:
+          case comparison::is_not_null:
+          {
+            break;
+          }
+          
+          case comparison::matches:
+          case comparison::does_not_match:
+          case comparison::hierarchally_matches:
+          case comparison::does_not_hierarchally_match:
+          {
+            new(&first.singleton_.join) std::unique_ptr<filter>(std::move(second.singleton_.join));
+            
+            break;
+          }
+        }
+        
+        break;
+      }
+      
+      case type::group:
+      {
+        new(&first.group_.children) std::list<filter>(std::move(second.group_.children));
+        first.group_.orlogic = second.group_.orlogic;
+        
+        break;
+      }
+    }
+    
+    second.~filter();
+    
+    second.type_ = tempType;
+    
+    switch (second.type_)
+    {
+      case type::empty:
+      {
+        break;
+      }
+      
+      case type::singleton:
+      {
+        new(&second.singleton_.filterField) field(std::move(tempField));
+        second.singleton_.filterType = tempComparison;
+        
+        switch (second.singleton_.filterType)
+        {
+          case comparison::int_equals:
+          case comparison::int_does_not_equal:
+          case comparison::int_is_at_least:
+          case comparison::int_is_greater_than:
+          case comparison::int_is_at_most:
+          case comparison::int_is_less_than:
+          {
+            second.singleton_.intValue = tempIntValue;
+            
+            break;
+          }
+          
+          case comparison::boolean_equals:
+          {
+            second.singleton_.boolValue = tempBoolValue;
+            
+            break;
+          }
+          
+          case comparison::string_equals:
+          case comparison::string_does_not_equal:
+          case comparison::string_is_like:
+          case comparison::string_is_not_like:
+          {
+            new(&second.singleton_.stringValue) std::string(std::move(tempStringValue));
+            
+            break;
+          }
+          
+          case comparison::is_null:
+          case comparison::is_not_null:
+          {
+            break;
+          }
+          
+          case comparison::matches:
+          case comparison::does_not_match:
+          case comparison::hierarchally_matches:
+          case comparison::does_not_hierarchally_match:
+          {
+            new(&second.singleton_.join) std::unique_ptr<filter>(std::move(tempJoin));
+            
+            break;
+          }
+        }
+        
+        break;
+      }
+      
+      case type::group:
+      {
+        new(&second.group_.children) std::list<filter>(std::move(tempChildren));
+        second.group_.orlogic = tempOrlogic;
+        
+        break;
+      }
+    }
+  }
+  
+  filter::~filter()
+  {
+    switch (type_)
+    {
+      case type::empty:
+      {
+        break;
+      }
+      
+      case type::singleton:
+      {
+        singleton_.filterField.~field();
+        
+        switch (singleton_.filterType)
+        {
+          case comparison::int_equals:
+          case comparison::int_does_not_equal:
+          case comparison::int_is_at_least:
+          case comparison::int_is_greater_than:
+          case comparison::int_is_at_most:
+          case comparison::int_is_less_than:
+          case comparison::boolean_equals:
+          case comparison::is_null:
+          case comparison::is_not_null:
+          {
+            break;
+          }
+          
+          case comparison::string_equals:
+          case comparison::string_does_not_equal:
+          case comparison::string_is_like:
+          case comparison::string_is_not_like:
+          {
+            using string_type = std::string;
+            
+            singleton_.stringValue.~string_type();
+            
+            break;
+          }
+          
+          case comparison::matches:
+          case comparison::does_not_match:
+          case comparison::hierarchally_matches:
+          case comparison::does_not_hierarchally_match:
+          {
+            using ptr_type = std::unique_ptr<filter>;
+            
+            singleton_.join.~ptr_type();
+            
+            break;
+          }
+        }
+        
+        break;
+      }
+      
+      case type::group:
+      {
+        using list_type = std::list<filter>;
+        
+        group_.children.~list_type();
+        
+        break;
+      }
+    }
+  }
+  
+  filter::filter()
+  {
+  }
+  
+  filter::filter(
+    field filterField,
+    comparison filterType,
+    int filterValue) :
+      type_(type::singleton)
+  {
+    if (filterField.getType() == field::type::integer)
+    {
+      switch (filterType)
+      {
+        case comparison::int_equals:
+        case comparison::int_does_not_equal:
+        case comparison::int_is_at_least:
+        case comparison::int_is_greater_than:
+        case comparison::int_is_at_most:
+        case comparison::int_is_less_than:
+        {
+          new(&singleton_.filterField) field(std::move(filterField));
+          singleton_.filterType = filterType;
+          singleton_.intValue = filterValue;
+          
+          break;
+        }
+        
+        case comparison::boolean_equals:
+        case comparison::string_equals:
+        case comparison::string_does_not_equal:
+        case comparison::string_is_like:
+        case comparison::string_is_not_like:
+        case comparison::is_null:
+        case comparison::is_not_null:
+        case comparison::matches:
+        case comparison::does_not_match:
+        case comparison::hierarchally_matches:
+        case comparison::does_not_hierarchally_match:
+        {
+          throw std::invalid_argument("Invalid comparison for integer field");
+        }
+      }
+    } else {
+      throw std::domain_error("Cannot match a non-integer field against an integer value");
+    }
+  }
+  
+  filter::filter(
+    field filterField,
+    comparison filterType,
+    std::string filterValue) :
+      type_(type::singleton)
+  {
+    if (filterField.getType() == field::type::string)
+    {
+      switch (filterType)
+      {
+        case comparison::string_equals:
+        case comparison::string_does_not_equal:
+        case comparison::string_is_like:
+        case comparison::string_is_not_like:
+        {
+          new(&singleton_.filterField) field(std::move(filterField));
+          singleton_.filterType = filterType;
+          new(&singleton_.stringValue) std::string(std::move(filterValue));
+          
+          break;
+        }
+        
+        case comparison::int_equals:
+        case comparison::int_does_not_equal:
+        case comparison::int_is_at_least:
+        case comparison::int_is_greater_than:
+        case comparison::int_is_at_most:
+        case comparison::int_is_less_than:
+        case comparison::boolean_equals:
+        case comparison::is_null:
+        case comparison::is_not_null:
+        case comparison::matches:
+        case comparison::does_not_match:
+        case comparison::hierarchally_matches:
+        case comparison::does_not_hierarchally_match:
+        {
+          throw std::invalid_argument("Invalid comparison for string field");
+        }
+      }
+    } else {
+      throw std::domain_error("Cannot match a non-string field against an string value");
+    }
+  }
+  
+  filter::filter(
+    field filterField,
+    comparison filterType,
+    bool filterValue) :
+      type_(type::singleton)
+  {
+    if (filterField.getType() == field::type::boolean)
+    {
+      switch (filterType)
+      {
+        case comparison::boolean_equals:
+        {
+          new(&singleton_.filterField) field(std::move(filterField));
+          singleton_.filterType = filterType;
+          singleton_.boolValue = filterValue;
+          
+          break;
+        }
+        
+        case comparison::string_equals:
+        case comparison::string_does_not_equal:
+        case comparison::string_is_like:
+        case comparison::string_is_not_like:
+        case comparison::int_equals:
+        case comparison::int_does_not_equal:
+        case comparison::int_is_at_least:
+        case comparison::int_is_greater_than:
+        case comparison::int_is_at_most:
+        case comparison::int_is_less_than:
+        case comparison::is_null:
+        case comparison::is_not_null:
+        case comparison::matches:
+        case comparison::does_not_match:
+        case comparison::hierarchally_matches:
+        case comparison::does_not_hierarchally_match:
+        {
+          throw std::invalid_argument("Invalid comparison for boolean field");
+        }
+      }
+    } else {
+      throw std::domain_error("Cannot match a non-boolean field against a boolean value");
+    }
+  }
+  
+  filter::filter(
+    field filterField,
+    comparison filterType) :
+      type_(type::singleton)
+  {
+    if (filterField.isNullable())
+    {
+      switch (filterType)
+      {
+        case comparison::is_null:
+        case comparison::is_not_null:
+        {
+          new(&singleton_.filterField) field(std::move(filterField));
+          singleton_.filterType = filterType;
+      
+          break;
+        }
+    
+        case comparison::string_equals:
+        case comparison::string_does_not_equal:
+        case comparison::string_is_like:
+        case comparison::string_is_not_like:
+        case comparison::int_equals:
+        case comparison::int_does_not_equal:
+        case comparison::int_is_at_least:
+        case comparison::int_is_greater_than:
+        case comparison::int_is_at_most:
+        case comparison::int_is_less_than:
+        case comparison::boolean_equals:
+        case comparison::matches:
+        case comparison::does_not_match:
+        case comparison::hierarchally_matches:
+        case comparison::does_not_hierarchally_match:
+        {
+          throw std::invalid_argument("Incorrect constructor for given comparison");
+        }
+      }
+    } else {
+      throw std::domain_error("Cannot check nullity/non-nullity of non-nullable field");
+    }
+  }
+  
+  filter::filter(
+    field joinOn,
+    comparison filterType,
+    filter joinCondition) :
+      type_(type::singleton)
+  {
+    switch (joinOn.getType())
+    {
+      case field::type::join:
+      case field::type::join_through:
+      {
+        switch (filterType)
+        {
+          case comparison::matches:
+          case comparison::does_not_match:
+          {
+            new(&singleton_.filterField) field(std::move(joinOn));
+            singleton_.filterType = filterType;
+            new(&singleton_.join) std::unique_ptr<filter>(new filter(joinCondition.normalize(singleton_.filterField.getJoinObject())));
+            
+            break;
+          }
+          
+          case comparison::int_equals:
+          case comparison::int_does_not_equal:
+          case comparison::int_is_at_least:
+          case comparison::int_is_greater_than:
+          case comparison::int_is_at_most:
+          case comparison::int_is_less_than:
+          case comparison::boolean_equals:
+          case comparison::string_equals:
+          case comparison::string_does_not_equal:
+          case comparison::string_is_like:
+          case comparison::string_is_not_like:
+          case comparison::is_null:
+          case comparison::is_not_null:
+          case comparison::hierarchally_matches:
+          case comparison::does_not_hierarchally_match:
+          {
+            throw std::invalid_argument("Incorrect constructor for given comparison");
+          }
+        }
+        
+        break;
+      }
+      
+      case field::type::hierarchal_join:
+      {
+        switch (filterType)
+        {
+          case comparison::hierarchally_matches:
+          case comparison::does_not_hierarchally_match:
+          {
+            new(&singleton_.filterField) field(std::move(joinOn));
+            singleton_.filterType = filterType;
+            new(&singleton_.join) std::unique_ptr<filter>(new filter(joinCondition.normalize(singleton_.filterField.getObject())));
+            
+            break;
+          }
+          
+          case comparison::int_equals:
+          case comparison::int_does_not_equal:
+          case comparison::int_is_at_least:
+          case comparison::int_is_greater_than:
+          case comparison::int_is_at_most:
+          case comparison::int_is_less_than:
+          case comparison::boolean_equals:
+          case comparison::string_equals:
+          case comparison::string_does_not_equal:
+          case comparison::string_is_like:
+          case comparison::string_is_not_like:
+          case comparison::is_null:
+          case comparison::is_not_null:
+          case comparison::matches:
+          case comparison::does_not_match:
+          {
+            throw std::invalid_argument("Incorrect constructor for given comparison");
+          }
+        }
+        
+        break;
+      }
+      
+      case field::type::undefined:
+      case field::type::string:
+      case field::type::integer:
+      case field::type::boolean:
+      {
+        throw std::domain_error("Matching field must be a join field");
+      }
+    }
+  }
+  
+  field filter::getField() const
+  {
+    if (type_ == type::singleton)
+    {
+      return singleton_.filterField;
+    } else {
+      throw std::domain_error("This filter does not have a field");
+    }
+  }
+  
+  filter::comparison filter::getComparison() const
+  {
+    if (type_ == type::singleton)
+    {
+      return singleton_.filterType;
+    } else {
+      throw std::domain_error("This filter does not have a comparison");
+    }
+  }
+  
+  filter filter::getJoinCondition() const
+  {
+    if (type_ == type::singleton)
+    {
+      switch (singleton_.filterType)
+      {
+        case comparison::matches:
+        case comparison::does_not_match:
+        case comparison::hierarchally_matches:
+        case comparison::does_not_hierarchally_match:
+        {
+          return *singleton_.join;
+        }
+        
+        case comparison::string_equals:
+        case comparison::string_does_not_equal:
+        case comparison::string_is_like:
+        case comparison::string_is_not_like:
+        case comparison::int_equals:
+        case comparison::int_does_not_equal:
+        case comparison::int_is_at_least:
+        case comparison::int_is_greater_than:
+        case comparison::int_is_at_most:
+        case comparison::int_is_less_than:
+        case comparison::boolean_equals:
+        case comparison::is_null:
+        case comparison::is_not_null:
+        {
+          throw std::domain_error("This filter does not have a join condition");
+        }
+      }
+    } else {
+      throw std::domain_error("This filter does not have a join condition");
+    }
+  }
+  
+  std::string filter::getStringArgument() const
+  {
+    if (type_ == type::singleton)
+    {
+      switch (singleton_.filterType)
+      {
+        case comparison::string_equals:
+        case comparison::string_does_not_equal:
+        case comparison::string_is_like:
+        case comparison::string_is_not_like:
+        {
+          return singleton_.stringValue;
+        }
+        
+        case comparison::int_equals:
+        case comparison::int_does_not_equal:
+        case comparison::int_is_at_least:
+        case comparison::int_is_greater_than:
+        case comparison::int_is_at_most:
+        case comparison::int_is_less_than:
+        case comparison::boolean_equals:
+        case comparison::is_null:
+        case comparison::is_not_null:
+        case comparison::matches:
+        case comparison::does_not_match:
+        case comparison::hierarchally_matches:
+        case comparison::does_not_hierarchally_match:
+        {
+          throw std::domain_error("This filter does not have a string argument");
+        }
+      }
+    } else {
+      throw std::domain_error("This filter does not have a string argument");
+    }
+  }
+  
+  int filter::getIntegerArgument() const
+  {
+    if (type_ == type::singleton)
+    {
+      switch (singleton_.filterType)
+      {
+        case comparison::int_equals:
+        case comparison::int_does_not_equal:
+        case comparison::int_is_at_least:
+        case comparison::int_is_greater_than:
+        case comparison::int_is_at_most:
+        case comparison::int_is_less_than:
+        {
+          return singleton_.intValue;
+        }
+        
+        case comparison::string_equals:
+        case comparison::string_does_not_equal:
+        case comparison::string_is_like:
+        case comparison::string_is_not_like:
+        case comparison::boolean_equals:
+        case comparison::is_null:
+        case comparison::is_not_null:
+        case comparison::matches:
+        case comparison::does_not_match:
+        case comparison::hierarchally_matches:
+        case comparison::does_not_hierarchally_match:
+        {
+          throw std::domain_error("This filter does not have an integer argument");
+        }
+      }
+    } else {
+      throw std::domain_error("This filter does not have an integer argument");
+    }
+  }
+  
+  bool filter::getBooleanArgument() const
+  {
+    if ((type_ == type::singleton) && (singleton_.filterType == comparison::boolean_equals))
+    {
+      return singleton_.boolValue;
+    } else {
+      throw std::domain_error("This filter does not have a boolean argument");
+    }
+  }
+  
+  filter::filter(bool orlogic) : type_(type::group)
+  {
+    new(&group_.children) std::list<filter>();
+    group_.orlogic = orlogic;
+  }
+  
+  bool filter::getOrlogic() const
+  {
+    if (type_ == type::group)
+    {
+      return group_.orlogic;
+    } else {
+      throw std::domain_error("This filter is not a group filter");
+    }
+  }
+  
+  filter filter::operator+(filter condition) const
+  {
+    filter result(*this);
+    result += std::move(condition);
+    
+    return result;
+  }
+  
+  filter& filter::operator+=(filter condition)
+  {
+    if (type_ == type::group)
+    {
+      group_.children.push_back(std::move(condition));
+      
+      return *this;
+    } else {
+      throw std::domain_error("Children can only be added to group filters");
+    }
+  }
+  
+  filter::const_iterator filter::begin() const
+  {
+    if (type_ == type::group)
+    {
+      return std::begin(group_.children);
+    } else {
+      throw std::domain_error("This filter has no children");
+    }
+  }
+  
+  filter::const_iterator filter::end() const
+  {
+    if (type_ == type::group)
+    {
+      return std::end(group_.children);
+    } else {
+      throw std::domain_error("This filter has no children");
+    }
+  }
+  
+  filter filter::operator!() const
+  {
+    switch (type_)
+    {
+      case type::empty:
+      {
+        return {};
+      }
+      
+      case type::singleton:
+      {
+        switch (singleton_.filterType)
+        {
+          case comparison::int_equals:
+          {
+            return filter(singleton_.filterField, comparison::int_does_not_equal, singleton_.intValue);
+          }
+          
+          case comparison::int_does_not_equal:
+          {
+            return filter(singleton_.filterField, comparison::int_equals, singleton_.intValue);
+          }
+          
+          case comparison::int_is_at_least:
+          {
+            return filter(singleton_.filterField, comparison::int_is_less_than, singleton_.intValue);
+          }
+          
+          case comparison::int_is_greater_than:
+          {
+            return filter(singleton_.filterField, comparison::int_is_at_most, singleton_.intValue);
+          }
+          
+          case comparison::int_is_at_most:
+          {
+            return filter(singleton_.filterField, comparison::int_is_greater_than, singleton_.intValue);
+          }
+          
+          case comparison::int_is_less_than:
+          {
+            return filter(singleton_.filterField, comparison::int_is_at_least, singleton_.intValue);
+          }
+          
+          case comparison::boolean_equals:
+          {
+            return filter(singleton_.filterField, comparison::boolean_equals, !singleton_.boolValue);
+          }
+          
+          case comparison::string_equals:
+          {
+            return filter(singleton_.filterField, comparison::string_does_not_equal, singleton_.stringValue);
+          }
+          
+          case comparison::string_does_not_equal:
+          {
+            return filter(singleton_.filterField, comparison::string_equals, singleton_.stringValue);
+          }
+          
+          case comparison::string_is_like:
+          {
+            return filter(singleton_.filterField, comparison::string_is_not_like, singleton_.stringValue);
+          }
+          
+          case comparison::string_is_not_like:
+          {
+            return filter(singleton_.filterField, comparison::string_is_like, singleton_.stringValue);
+          }
+          
+          case comparison::is_null:
+          {
+            return filter(singleton_.filterField, comparison::is_not_null);
+          }
+          
+          case comparison::is_not_null:
+          {
+            return filter(singleton_.filterField, comparison::is_null);
+          }
+          
+          case comparison::matches:
+          {
+            return filter(singleton_.filterField, comparison::does_not_match, *singleton_.join);
+          }
+          
+          case comparison::does_not_match:
+          {
+            return filter(singleton_.filterField, comparison::matches, *singleton_.join);
+          }
+          
+          case comparison::hierarchally_matches:
+          {
+            return filter(singleton_.filterField, comparison::does_not_hierarchally_match, *singleton_.join);
+          }
+          
+          case comparison::does_not_hierarchally_match:
+          {
+            return filter(singleton_.filterField, comparison::hierarchally_matches, *singleton_.join);
+          }
+        }
+      }
+      
+      case type::group:
+      {
+        filter result(!group_.orlogic);
+        
+        for (const filter& child : group_.children)
+        {
+          result += !child;
+        }
+        
+        return result;
+      }
+    }
+  }
+  
+  filter& filter::operator&=(filter condition)
+  {
+    return (*this = (*this && std::move(condition)));
+  }
+  
+  filter& filter::operator|=(filter condition)
+  {
+    return (*this = (*this || std::move(condition)));
+  }
+  
+  filter filter::operator&&(filter condition) const
+  {
+    switch (type_)
+    {
+      case type::empty:
+      {
+        return condition;
+      }
+      
+      case type::singleton:
+      {
+        filter result(false);
+        result.group_.children.push_back(*this);
+        result.group_.children.push_back(std::move(condition));
+        
+        return result;
+      }
+      
+      case type::group:
+      {
+        if (group_.orlogic)
+        {
+          filter result(false);
+          result.group_.children.push_back(*this);
+          result.group_.children.push_back(std::move(condition));
+
+          return result;
+        } else {
+          filter result(*this);
+          result.group_.children.push_back(std::move(condition));
+          
+          return result;
+        }
+      }
+    }
+  }
+  
+  filter filter::operator||(filter condition) const
+  {
+    switch (type_)
+    {
+      case type::empty:
+      {
+        return condition;
+      }
+      
+      case type::singleton:
+      {
+        filter result(true);
+        result.group_.children.push_back(*this);
+        result.group_.children.push_back(std::move(condition));
+        
+        return result;
+      }
+      
+      case type::group:
+      {
+        if (!group_.orlogic)
+        {
+          filter result(true);
+          result.group_.children.push_back(*this);
+          result.group_.children.push_back(std::move(condition));
+
+          return result;
+        } else {
+          filter result(*this);
+          result.group_.children.push_back(std::move(condition));
+          
+          return result;
+        }
+      }
+    }
+  }
+  
+  filter filter::normalize(object context) const
+  {
+    {
+      switch (type_)
+      {
+        case type::empty:
+        {
+          return *this;
+        }
+
+        case type::singleton:
+        {
+          // First, switch on the normalized context, and then switch on the
+          // current context. We recursively recontextualize by using the
+          // current filter as a subquery for a join such that the context of
+          // the subquery is one step closer to the context of the current
+          // filter, and then letting the filter constructor normalize the
+          // subquery.
+          switch (context)
+          {
+            case object::undefined:
+            {
+              // An undefined object indicates no participation in
+              // recontexualization.
+              return *this;
+            }
+            
+            case object::notion:
+            {
+              switch (singleton_.filterField.getObject())
+              {
+                case object::undefined:
+                case object::notion:
+                {
+                  return *this;
+                }
+                
+                case object::word:
+                case object::group:
+                case object::frame:
+                case object::lemma:
+                case object::form:
+                case object::pronunciation:
+                {
+                  return (verbly::notion::word %= *this);
+                }
+              }
+            }
+              
+            case object::word:
+            {
+              switch (singleton_.filterField.getObject())
+              {
+                case object::notion:
+                {
+                  return (verbly::word::notion %= *this);
+                }
+                
+                case object::undefined:
+                case object::word:
+                {
+                  return *this;
+                }
+                
+                case object::group:
+                case object::frame:
+                {
+                  return (verbly::word::group %= *this);
+                }
+                
+                case object::lemma:
+                case object::form:
+                case object::pronunciation:
+                {
+                  return (verbly::word::lemma %= *this);
+                }
+              }
+              
+              case object::group:
+              {
+                switch (singleton_.filterField.getObject())
+                {
+                  case object::undefined:
+                  case object::group:
+                  {
+                    return *this;
+                  }
+                  
+                  case object::notion:
+                  case object::word:
+                  case object::lemma:
+                  case object::form:
+                  case object::pronunciation:
+                  {
+                    return (verbly::group::word %= *this);
+                  }
+                  
+                  case object::frame:
+                  {
+                    return (verbly::group::frame %= *this);
+                  }
+                }
+              }
+              
+              case object::frame:
+              {
+                switch (singleton_.filterField.getObject())
+                {
+                  case object::undefined:
+                  case object::frame:
+                  {
+                    return *this;
+                  }
+                
+                  case object::notion:
+                  case object::word:
+                  case object::group:
+                  case object::lemma:
+                  case object::form:
+                  case object::pronunciation:
+                  {
+                    return (verbly::frame::group %= *this);
+                  }
+                }
+              }
+              
+              case object::lemma:
+              {
+                switch (singleton_.filterField.getObject())
+                {
+                  case object::notion:
+                  case object::word:
+                  case object::group:
+                  case object::frame:
+                  {
+                    return verbly::lemma::word %= *this;
+                  }
+                  
+                  case object::undefined:
+                  case object::lemma:
+                  {
+                    return *this;
+                  }
+
+                  case object::form:
+                  case object::pronunciation:
+                  {
+                    return (verbly::lemma::form(inflection::base) %= *this);
+                  }
+                }
+              }
+              
+              case object::form:
+              {
+                switch (singleton_.filterField.getObject())
+                {
+                  case object::notion:
+                  case object::word:
+                  case object::group:
+                  case object::frame:
+                  case object::lemma:
+                  {
+                    return verbly::form::lemma(inflection::base) %= *this;
+                  }
+                  
+                  case object::undefined:
+                  case object::form:
+                  {
+                    return *this;
+                  }
+
+                  case object::pronunciation:
+                  {
+                    return (verbly::form::pronunciation %= *this);
+                  }
+                }
+              }
+              
+              case object::pronunciation:
+              {
+                switch (singleton_.filterField.getObject())
+                {
+                  case object::notion:
+                  case object::word:
+                  case object::group:
+                  case object::frame:
+                  case object::lemma:
+                  case object::form:
+                  {
+                    return verbly::pronunciation::form %= *this;
+                  }
+                  
+                  case object::undefined:
+                  case object::pronunciation:
+                  {
+                    return *this;
+                  }
+                }
+              }
+            }
+          }
+        }
+
+        case type::group:
+        {
+          filter result(group_.orlogic);
+          std::map<field, filter> joins;
+
+          for (const filter& child : group_.children)
+          {
+            filter normalized = child.normalize(context);
+
+            // Notably, this does not attempt to merge hierarchal matches.
+            switch (normalized.getType())
+            {
+              case type::singleton:
+              {
+                switch (normalized.getComparison())
+                {
+                  case comparison::matches:
+                  {
+                    if (!joins.count(normalized.singleton_.filterField))
+                    {
+                      joins[normalized.getField()] = filter(group_.orlogic);
+                    }
+
+                    joins.at(normalized.getField()) += std::move(*normalized.singleton_.join);
+                    
+                    break;
+                  }
+                  
+                  case comparison::does_not_match:
+                  {
+                    if (!joins.count(normalized.singleton_.filterField))
+                    {
+                      joins[normalized.getField()] = filter(group_.orlogic);
+                    }
+
+                    joins.at(normalized.getField()) += !*normalized.singleton_.join;
+                    
+                    break;
+                  }
+                  
+                  case comparison::int_equals:
+                  case comparison::int_does_not_equal:
+                  case comparison::int_is_at_least:
+                  case comparison::int_is_greater_than:
+                  case comparison::int_is_at_most:
+                  case comparison::int_is_less_than:
+                  case comparison::boolean_equals:
+                  case comparison::string_equals:
+                  case comparison::string_does_not_equal:
+                  case comparison::string_is_like:
+                  case comparison::string_is_not_like:
+                  case comparison::is_null:
+                  case comparison::is_not_null:
+                  case comparison::hierarchally_matches:
+                  case comparison::does_not_hierarchally_match:
+                  {
+                    result += std::move(normalized);
+                    
+                    break;
+                  }
+                }
+                
+                break;
+              }
+              
+              case type::group:
+              case type::empty:
+              {
+                result += std::move(normalized);
+                
+                break;
+              }
+            }
+          }
+
+          for (auto& mapping : joins)
+          {
+            const field& joinOn = mapping.first;
+            filter& joinCondition = mapping.second;
+
+            result += (joinOn %= joinCondition.normalize(joinOn.getJoinObject()));
+          }
+
+          return result;
+        }
+      }
+    }
+  }
+
+};