func (d *Dwimmer) Answer(q term.T, optionalSetting ...*term.SettingT) (term.T, term.T) {
var s *term.SettingT
if len(optionalSetting) == 1 {
s = optionalSetting[0]
} else {
s = term.InitT()
s.AppendTerm(BuiltinAnswerer.T(q))
}
a := dynamics.SubRun(d, q, s)
switch a.Head() {
case core.Answer:
return a.Values()[0], nil
case core.Yes, core.No:
return a, nil
}
follow := term.InitT()
isAnswer := dynamics.SubRun(d, IsAnswer.T(a, q), s, follow)
for {
switch isAnswer.Head() {
case core.Yes:
result, err := d.Answer(WhatAnswer.T(a, q))
if err != nil {
return nil, a
}
return result, nil
case core.No:
return nil, a
}
isAnswer = dynamics.SubRun(d, IsAnswerClarify.T(), s, follow)
}
}
func RunDefaultInitializers(d dynamics.Dwimmer) {
s := term.InitT()
s.AppendTerm(Initialization.T())
for _, t := range dynamics.DefaultInitializers {
c := term.InitT()
dynamics.SubRun(d, t, s, c)
}
}
func (d *Dwimmer) watchdog(setting *term.SettingT) {
if rand.Int()%(watchFrequency<<(3*watcherDepth)) == 0 {
watcherDepth++
defer func() { watcherDepth-- }()
parent := setting.Copy().AppendAction(term.MetaC())
oldWatcher := d.lastWatcher
newWatcher := term.InitT()
var Q term.T
if d.lastWatcher == nil {
Q = IsAllWell.T(term.MakeChannel(parent))
} else {
Q = IsAllWellPred.T(term.MakeChannel(parent), term.MakeChannel(oldWatcher))
}
d.lastWatcher = newWatcher
dynamics.SubRun(d, Q, parent, newWatcher)
}
}
func ElicitAction(d dynamics.Dwimmer, context *term.SettingT, setting *term.Setting) dynamics.Transition {
for {
Q := FallThrough.T(represent.Setting(setting))
result := dynamics.SubRun(d, Q, context)
switch result.Head() {
case TakeTransition:
transition, err := represent.ToTransition(d, result.Values()[0])
if err == nil {
return transition
}
case core.OK:
default:
result, err := d.Answer(TransitionGiven.T(result, Q))
if err == nil {
transition, err := represent.ToTransition(d, result)
if err == nil {
return transition
}
}
}
}
}
func (d *Dwimmer) Do(a term.ActionT, s *term.SettingT) term.T {
switch a.Act {
case term.Return:
return a.Args[0]
case term.Ask:
Q := a.Args[0]
child := term.InitT()
dynamics.SubRun(d, Q, s, child)
return nil
case term.View:
value := a.Args[0]
if value != nil {
s.AppendTerm(value)
} else {
s.AppendTerm(Closed.T())
}
return nil
case term.Replace:
//value := a.Args[0]
//n := a.IntArgs[0]
//s.Rollback(n).AppendTerm(value)
return nil
case term.Replay:
n := a.IntArgs[0]
s.Rollback(n)
return nil
case term.Clarify:
Q := a.Args[1]
//TODO handle null pointers much better...
//(e.g. one part of an expression may refer to a deleted variable)
if a.Args[0] == nil {
s.AppendTerm(Closed.T())
return nil
}
var target *term.SettingT
channel, err := represent.ToChannel(d, a.Args[0])
if err == nil {
target = channel.(term.Channel).Instantiate()
} else {
var othererr term.T
target, othererr = represent.ToSettingT(d, a.Args[0])
if othererr != nil {
s.AppendTerm(NotAChannel.T(err))
return nil
}
}
dynamics.SubRun(d, Q, s, target)
return nil
case term.Correct:
n := a.IntArgs[0]
old := s.Setting.Rollback(n)
transition := ElicitAction(d, term.InitT(), old)
d.Save(old, transition)
s.AppendTerm(core.OK.T())
return nil
case term.Delete:
n := a.IntArgs[0]
s.Args[n] = nil
s.AppendTerm(core.OK.T())
return nil
case term.Meta:
s.AppendTerm(CurrentSetting.T(represent.SettingT(s)))
return nil
}
panic("unknown kind of action")
}