'added 1 edge':
  format: 'fbp'
  from: |
    'default' -> IN read(ReadSomething)
    unconnected(Frobnitzer)
  to: |
    'default' -> IN read(ReadSomething)
    read OUT -> IN unconnected(Frobnitzer)
  diff: "+ read OUT -> IN unconnected"

'removed 1 edge':
  format: 'fbp'
  from: |
    'default' -> IN read(ReadSomething)
    read OUT -> IN unconnected(Frobnitzer)
  to: |
    'default' -> IN read(ReadSomething)
    unconnected(Frobnitzer)
  diff: "- read OUT -> IN unconnected"

'add a string IIP':
  format: 'fbp'
  from: |
    read(ReadSomething)
  to: |
    'myiip' -> read(ReadSomething)
  diff: '+ "myiip" -> IN read'

'remove a string IIP':
  format: 'fbp'
  from: |
    'myiip' -> read(ReadSomething)
  to: |
    read(ReadSomething)
  diff: '- "myiip" -> IN read'