6 Basics
  
  
  6.1 Categories
  
  6.1-1 IsStructureObjectOrObjectOrMorphism
  
  IsStructureObjectOrObjectOrMorphism( arg )  filter
  Returns:  true or false
  
  This  is  the super super GAP-category which will include the GAP-categories
  IsStructureObjectOrObject and IsHomalgObjectOrMorphism
  
  6.1-2 IsStructureObjectOrObject
  
  IsStructureObjectOrObject( arg )  filter
  Returns:  true or false
  
  This  is  the  super  GAP-category  which  will  include  the GAP-categories
  IsHomalgRing, IsHomalgModule, IsHomalgRingOrModule and IsHomalgComplex
  
  6.1-3 IsStructureObject
  
  IsStructureObject( arg )  filter
  Returns:  true or false
  
  This  is  the  super  GAP-category  which  will  include  the GAP-categories
  IsHomalgRing  we  need  this  GAP-category to define things like Hom(M,R) as
  easy  as  Hom(M,N)  without  distinguishing  between structure objects (e.g.
  rings) and objects (e.g. modules)
  
  6.1-4 IsStructureObjectMorphism
  
  IsStructureObjectMorphism( arg )  filter
  Returns:  true or false
  
  This  is  the  super  GAP-category  which  will  include  the GAP-categories
  IsHomalgRingMap, etc.
  
  6.1-5 IsHomalgRingOrModule
  
  IsHomalgRingOrModule( arg )  filter
  Returns:  true or false
  
  this  is  the  super  GAP-category  which  will  include  the GAP-categories
  IsHomalgRing, IsHomalgModule: