terraform/dag/edge.go

38 lines
687 B
Go

package dag
import (
"fmt"
)
// Edge represents an edge in the graph, with a source and target vertex.
type Edge interface {
Source() Vertex
Target() Vertex
Hashable
}
// BasicEdge returns an Edge implementation that simply tracks the source
// and target given as-is.
func BasicEdge(source, target Vertex) Edge {
return &basicEdge{S: source, T: target}
}
// basicEdge is a basic implementation of Edge that has the source and
// target vertex.
type basicEdge struct {
S, T Vertex
}
func (e *basicEdge) Hashcode() interface{} {
return fmt.Sprintf("%p-%p", e.S, e.T)
}
func (e *basicEdge) Source() Vertex {
return e.S
}
func (e *basicEdge) Target() Vertex {
return e.T
}