Try making Taggable interface more abstract

docs/src/interfaces.md

@@ -24,16 +24,14 @@ A type implementing the `Network` interface must implement the following methods
 
 The following methods have a default implementation or their implementation is optional.
 
-| Method              | When should this method be defined?                  | Default definition    | Brief description                                      |
-| :------------------ | :--------------------------------------------------- | :-------------------- | :----------------------------------------------------- |
-| `vertex_type(g)`    | If your vertex type is type-stable                   | `Any`                 | Returns the type used for representing a vertex        |
-| `edge_type(g)`      | If your edge type is type-stable                     | `Any`                 | Returns the type used for representing an edge         |
-| `hasvertex(g, v)`   | If there is a more performant way                    | `v in vertices(g)`    | Returns `true` if vertex `v` is present in network `g` |
-| `hasedge(g, e)`     | If there is a more performant way                    | `e in edges(g)`       | Returns `true` if edge `e` is present in network `e`   |
-| `nvertices(g)`      | If there is a more performant way                    | `length(vertices(g))` | Returns the number of vertices present in the network  |
-| `nedges(g)`         | If there is a more performant way                    | `length(edges(g))`    | Returns the number of edges present in the network     |
-| `vertex_at(g, tag)` | If your type has some other way to refer to a vertex | _(undefined)_         | Returns the vertex related to `tag`                    |
-| `edge_at(g, tag)`   | If your type has some other way to refer to an edge  | _(undefined)_         | Returns the edge related to `tag`                      |
+| Method            | When should this method be defined? | Default definition    | Brief description                                      |
+| :---------------- | :---------------------------------- | :-------------------- | :----------------------------------------------------- |
+| `vertex_type(g)`  | If your vertex type is type-stable  | `Any`                 | Returns the type used for representing a vertex        |
+| `edge_type(g)`    | If your edge type is type-stable    | `Any`                 | Returns the type used for representing an edge         |
+| `hasvertex(g, v)` | If there is a more performant way   | `v in vertices(g)`    | Returns `true` if vertex `v` is present in network `g` |
+| `hasedge(g, e)`   | If there is a more performant way   | `e in edges(g)`       | Returns `true` if edge `e` is present in network `e`   |
+| `nvertices(g)`    | If there is a more performant way   | `length(vertices(g))` | Returns the number of vertices present in the network  |
+| `nedges(g)`       | If there is a more performant way   | `length(edges(g))`    | Returns the number of edges present in the network     |
 
 ### Mutating methods
 
@@ -56,6 +54,11 @@ The [`EdgePersistence`](@ref Networks.EdgePersistence) trait defines the behavio
 
 WIP
 
+| Required method     | Description                         |
+| :------------------ | :---------------------------------- |
+| `vertex_at(g, tag)` | Returns the vertex related to `tag` |
+| `edge_at(g, tag)`   | Returns the edge related to `tag`   |
+
 ## Attributeable
 
 WIP

src/Interfaces/Network.jl

@@ -68,11 +68,6 @@ Returns the edges connected to vertex `v` in `graph`.
 """
 function vertex_incidents end
 
-function vertex_at end
-function edge_at end
-
-:(Base.copy)
-
 # query methods with default implementation
 """
     vertex_type(graph)
@@ -253,16 +248,6 @@ function nedges(graph, ::DontDelegate)
     return length(edges(graph))
 end
 
-## `vertex_at`
-vertex_at(graph, tag) = vertex_at(graph, tag, DelegatorTrait(Network(), graph))
-vertex_at(graph, tag, ::DelegateToField) = vertex_at(delegator(Network(), graph), tag)
-vertex_at(graph, tag, ::DontDelegate) = throw(MethodError(vertex_at, (graph, tag)))
-
-## `edge_at`
-edge_at(graph, tag) = edge_at(graph, tag, DelegatorTrait(Network(), graph))
-edge_at(graph, tag, ::DelegateToField) = edge_at(delegator(Network(), graph), tag)
-edge_at(graph, tag, ::DontDelegate) = throw(MethodError(edge_at, (graph, tag)))
-
 ## `edges_set_strand`
 edges_set_strand(graph) = edges_set_strand(graph, DelegatorTrait(Network(), graph))
 edges_set_strand(graph, ::DelegateToField) = edges_set_strand(delegator(Network(), graph))

src/Interfaces/Taggable.jl

@@ -1,4 +1,4 @@
-struct Taggable <: Interface end
+struct Taggable{T} <: Interface end
 
 # traits
 # WARN experimental
@@ -24,6 +24,9 @@ function untag! end
 function replace_tag! end
 
 # query methods
+function vertex_at end
+function edge_at end
+
 function vertex_tags end
 function edge_tags end
 
@@ -56,6 +59,16 @@ hastag(graph, tag, ::EdgeTagKind) = has_edge_tag(graph, tag)
 tag_at(graph, v::AbstractVertex) = tag_at_vertex(graph, v)
 tag_at(graph, e::AbstractEdge) = tag_at_edge(graph, e)
 
+## `vertex_at`
+vertex_at(graph, tag) = vertex_at(graph, tag, DelegatorTrait(Network(), graph))
+vertex_at(graph, tag, ::DelegateToField) = vertex_at(delegator(Network(), graph), tag)
+vertex_at(graph, tag, ::DontDelegate) = throw(MethodError(vertex_at, (graph, tag)))
+
+## `edge_at`
+edge_at(graph, tag) = edge_at(graph, tag, DelegatorTrait(Network(), graph))
+edge_at(graph, tag, ::DelegateToField) = edge_at(delegator(Network(), graph), tag)
+edge_at(graph, tag, ::DontDelegate) = throw(MethodError(edge_at, (graph, tag)))
+
 ## `replace_tag!`
 replace_tag!(graph, old, new) = replace_tag!(graph, old, new, TagKind(old), TagKind(new))
 replace_tag!(graph, old, new, ::VertexTagKind, ::VertexTagKind) = replace_vertex_tag!(graph, old, new)