GraphOptionFn

Implemented by functor values that set properties on a GraphOptions instance, which are then used by Graphs NewGraph/Graph.Subgraph to configure new [sub]graphs.

A nil error is expected as a return value if the functor has successfully set the options it is intended to.

These functors are usually returned by With* functions that are free to accept any parameters to be used within the functor, e.g.

func WithMyOptions(id string) GraphOptionFn {
  return func(options GraphOptions) error {
    // use the given id
    options.SetID(id)
    // always create as strict
    options.SetStrict(true)
    // use undirected (graph) instead of the default directed (digraph)
    options.SetType(GraphTypeUndirected)

    return nil
  }
}

then it can be used as

graph, _ := dot.New(WithMyOptions("some-id"))

implementation

// GraphOptionFn is a functor that mutates graph options
type GraphOptionFn func(GraphOptions) error

source

package dot

import (
    "github.com/wwmoraes/dot/attributes"
)

// GraphOptionFn is a functor that mutates graph options
type GraphOptionFn func(GraphOptions) error

// NodeInitializerFn mutates Nodes during their creation time
type NodeInitializerFn func(Node)

// EdgeInitializerFn mutates Edges during their creation time
type EdgeInitializerFn func(StyledEdge)

// Graph is implemented by dot-compatible graph values
type Graph interface {
    attributes.Identity
    attributes.Styleable
    attributes.Serializable

    // Root returns the root graph (i.e. the topmost, without a parent graph)
    Root() Graph
    // Type returns the graph type: directed, undirected or sub
    Type() GraphType
    // FindSubgraph returns the subgraph of this graph or from one of its parents
    FindSubgraph(id string) (Graph, bool)
    // Subgraph creates a subgraph of this graph
    Subgraph(optionsFn ...GraphOptionFn) (Graph, error)
    // Node gets a node by id, or creates a new one if it doesn't exist
    Node(id string) Node
    // Edge creates a new edge between the two provided nodes
    Edge(n1, n2 Node) StyledEdge
    // Edge creates a new edge between the two provided nodes, and also set the
    // given attributes
    EdgeWithAttributes(n1, n2 Node, attributes attributes.Reader) StyledEdge
    // FindEdges gets all edges in the graph between the two provided nodes
    FindEdges(fromNode, toNode Node) (found []Edge)
    // FindNode gets a node by id
    FindNode(id string) (Node, bool)
    // VisitNodes runs the provided function on all nodes recursively
    VisitNodes(callback func(node Node) (done bool))
    // AddToSameRank adds the given nodes to the specified rank group, forcing
    // them to be rendered in the same row
    AddToSameRank(group string, nodes ...Node)
    // FindNodeByID return node by id
    FindNodeByID(id string) (foundNode Node, found bool)
    // FindNodes returns all nodes recursively
    FindNodes() (nodes []Node)
    // HasSubgraphs returns true if the graph has any subgraphs
    HasSubgraphs() bool
    // HasNodes returns true if the graph has any nodes
    HasNodes() bool
    // HasEdges returns true if the graph has any nodes
    HasEdges() bool
    // HasSameRankNodes returns true if the graph has nodes grouped as same rank
    HasSameRankNodes() bool
    // IsStrict return true if the graph is set as strict
    IsStrict() bool
}