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2 Category of presheaves (with bounds) of a (linear) category
 2.1 GAP categories
 2.2 Attributes
 2.3 Constructors
 2.4 Operations

2 Category of presheaves (with bounds) of a (linear) category

Here we assume that the object set of the source category carries a discrete total order. This code is temporary and should at some point in the future be replaced by something like "presheaves with bounded support".

2.1 GAP categories

2.1-1 IsPreSheafWithBoundsCategory
‣ IsPreSheafWithBoundsCategory( category )( filter )

Returns: true or false

The GAP category of a presheaf category.

2.1-2 IsCellInPreSheafWithBoundsCategory
‣ IsCellInPreSheafWithBoundsCategory( cell )( filter )

Returns: true or false

The GAP category of cells in a presheaf category.

2.1-3 IsObjectInPreSheafWithBoundsCategory
‣ IsObjectInPreSheafWithBoundsCategory( obj )( filter )

Returns: true or false

The GAP category of objects in a presheaf category.

2.1-4 IsMorphismInPreSheafWithBoundsCategory
‣ IsMorphismInPreSheafWithBoundsCategory( mor )( filter )

Returns: true or false

The GAP category of morphisms in a presheaf category.

2.2 Attributes

2.2-1 Source
‣ Source( PSh )( attribute )

Returns: a CAP category

The source category \(C\) of the presheaf category PSh=PSh(\(C,V\)).

2.2-2 Target
‣ Target( PSh )( attribute )

Returns: a CAP category

The target category \(V\) of the presheaf category PSh=PSh(\(C,V\)).

2.2-3 OppositeOfSource
‣ OppositeOfSource( Hom )( attribute )

Returns: a CAP category

The opposite \(C^\mathrm{op}\) of the source category \(C\) of the presheaf category PSh=PSh(\(C,V\)).

2.2-4 Source
‣ Source( F )( attribute )

Returns: a CAP category

The source of the presheaf F.

2.2-5 Target
‣ Target( F )( attribute )

Returns: a CAP category

The target of the presheaf F.

2.2-6 YonedaEmbedding
‣ YonedaEmbedding( B )( attribute )

Returns: a CAP functor

2.2-7 YonedaEmbeddingOfSourceCategory
‣ YonedaEmbeddingOfSourceCategory( PSh )( attribute )

Returns: a CAP functor

2.2-8 CoYonedaLemmaOnObjects
‣ CoYonedaLemmaOnObjects( F )( attribute )

2.2-9 CoYonedaLemmaOnMorphisms
‣ CoYonedaLemmaOnMorphisms( phi )( attribute )

2.3 Constructors

2.3-1 PreSheavesWithBounds
‣ PreSheavesWithBounds( B, C )( operation )
‣ PreSheavesWithBounds( B )( operation )

Returns: a CAP category

Construct the category Hom( B^op, C ) of functors from the opposite of the small category B to the category C as objects and their natural transformations as morphisms.

2.4 Operations

2.4-1 ApplyObjectInPreSheafCategoryToObject
‣ ApplyObjectInPreSheafCategoryToObject( F, obj )( operation )

Returns: a CAP object

Apply the presheaf F to the object obj. The shorthand is F(obj).

2.4-2 ApplyObjectInPreSheafCategoryToMorphism
‣ ApplyObjectInPreSheafCategoryToMorphism( F, mor )( operation )

Returns: a CAP morphism

Apply the presheaf F to the morphism mor. The shorthand is F(mor).

2.4-3 ApplyMorphismInPreSheafCategoryToObject
‣ ApplyMorphismInPreSheafCategoryToObject( eta, obj )( operation )

Returns: a CAP morphism

Apply the presheaf morphism eta to the object obj. The shorthand is eta(o).

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