fixed SetRangeCategoryOfHomomorphismStructure for the opposite category

SetRangeCategoryOfHomomorphismStructure only if
the operations of the homomorphism structure can be installed

resolves #1249

Author: mohamed-barakat

CAP/PackageInfo.g

@@ -10,7 +10,7 @@ SetPackageInfo( rec(
 
 PackageName := "CAP",
 Subtitle := "Categories, Algorithms, Programming",
-Version := "2023.02-06",
+Version := "2023.02-07",
 Date := Concatenation( "01/", ~.Version{[ 6, 7 ]}, "/", ~.Version{[ 1 .. 4 ]} ),
 License := "GPL-2.0-or-later",
 

CAP/examples/OppositeCategory.g

@@ -12,8 +12,9 @@ ListKnownCategoricalProperties( op );
 #!   "IsAbelianCategoryWithEnoughProjectives", "IsAdditiveCategory",
 #!   "IsBraidedMonoidalCategory", "IsClosedMonoidalCategory",
 #!   "IsCoclosedMonoidalCategory", "IsEnrichedOverCommutativeRegularSemigroup",
-#!   "IsLinearCategoryOverCommutativeRing", "IsMonoidalCategory",
-#!   "IsPreAbelianCategory", "IsRigidSymmetricClosedMonoidalCategory",
+#!   "IsEquippedWithHomomorphismStructure", "IsLinearCategoryOverCommutativeRing",
+#!   "IsMonoidalCategory", "IsPreAbelianCategory",
+#!   "IsRigidSymmetricClosedMonoidalCategory",
 #!   "IsRigidSymmetricCoclosedMonoidalCategory", "IsSkeletalCategory",
 #!   "IsStrictMonoidalCategory", "IsSymmetricClosedMonoidalCategory",
 #!   "IsSymmetricCoclosedMonoidalCategory", "IsSymmetricMonoidalCategory" ]

CAP/gap/OppositeCategory.gi

@@ -59,8 +59,9 @@ end );
 BindGlobal( "CAP_INTERNAL_INSTALL_OPPOSITE_ADDS_FROM_CATEGORY",
 
   function( opposite_category, category )
-    local only_primitive_operations, recnames, current_recname, current_entry, dual_operation_name,
-          filter_list, input_arguments_names, return_type, func_string,
+    local only_primitive_operations, recnames, list_of_installed_operations,
+          operations_of_homomorphism_structure, operations_of_external_hom,
+          current_recname, current_entry, dual_operation_name, filter_list, input_arguments_names, return_type, func_string,
           dual_preprocessor_func_string, preprocessor_string, dual_arguments, tmp,
           dual_postprocessor_func_string, postprocessor_string, output_source_getter_string, output_range_getter_string, return_statement,
           func, weight, current_add, list_of_attributes, attr, tester, setter, getter;
@@ -69,7 +70,7 @@ BindGlobal( "CAP_INTERNAL_INSTALL_OPPOSITE_ADDS_FROM_CATEGORY",
 
     ## Take care of attributes
     ## TODO: if there are more instances, set markers in the MethodRecord
-    list_of_attributes := [ "RangeCategoryOfHomomorphismStructure", "CommutativeRingOfLinearCategory" ];
+    list_of_attributes := [ "CommutativeRingOfLinearCategory" ];
 
     for attr in list_of_attributes do
 
@@ -97,6 +98,30 @@ BindGlobal( "CAP_INTERNAL_INSTALL_OPPOSITE_ADDS_FROM_CATEGORY",
                           "VerticalPostCompose",
                           "IdenticalTwoCell" ] );
 
+    if only_primitive_operations then
+        list_of_installed_operations := ListPrimitivelyInstalledOperationsOfCategory( category );
+    else
+        list_of_installed_operations := ListInstalledOperationsOfCategory( category );
+    fi;
+    
+    operations_of_homomorphism_structure :=
+      [ "DistinguishedObjectOfHomomorphismStructure",
+        "HomomorphismStructureOnObjects",
+        "HomomorphismStructureOnMorphisms",
+        "HomomorphismStructureOnMorphismsWithGivenObjects",
+        "InterpretMorphismAsMorphismFromDistinguishedObjectToHomomorphismStructure",
+        "InterpretMorphismAsMorphismFromDistinguishedObjectToHomomorphismStructureWithGivenObjects",
+        "InterpretMorphismFromDistinguishedObjectToHomomorphismStructureAsMorphism",
+        ];
+    
+    if HasRangeCategoryOfHomomorphismStructure( category ) and
+       not IsEmpty( Intersection( list_of_installed_operations, operations_of_homomorphism_structure ) ) then
+        
+        SetRangeCategoryOfHomomorphismStructure( opposite_category, RangeCategoryOfHomomorphismStructure( category ) );
+        SetIsEquippedWithHomomorphismStructure( opposite_category, true );
+        
+    fi;
+    
     for current_recname in recnames do
 
         current_entry := CAP_INTERNAL_METHOD_NAME_RECORD.( current_recname );
@@ -116,7 +141,7 @@ BindGlobal( "CAP_INTERNAL_INSTALL_OPPOSITE_ADDS_FROM_CATEGORY",
             continue;
         fi;
 
-        if only_primitive_operations and not dual_operation_name in ListPrimitivelyInstalledOperationsOfCategory( category ) then
+        if not dual_operation_name in list_of_installed_operations then
             continue;
         fi;