// 执行 val 到 to 类型, 并赋值到 to
func (p *Group) SetTo(to interface{}, args ...interface{}) (err error) {
var val interface{}
if len(args) > 0 {
val = args[0]
}
v := proto.ValueOf(val)
if !v.IsValid() {
return toInValidArgs(v)
}
return nil
}
// 执行 val 到 like 类型, 并返回 interface{},args 是附加的参数
func (p *Group) To(like interface{}, args ...interface{}) (i interface{}, err error) {
defer func() {
if e := recover(); e != nil {
err = errors.New(fmt.Sprint(e))
}
}()
if len(args) == 0 {
return nil, toInValidArgs("arguments length is zero")
}
c := p.match(like, args)
if c == nil {
return nil, toNotSupported(like)
}
// 单函数
if len(c.queue) == 0 {
in := []reflect.Value{}
for _, arg := range args {
in = append(in, proto.ValueOf(arg))
}
out := c.apply.Call(in)
ify := len(out) - 1
if ify < 0 || out[0].Kind().String() != proto.TypeOf(like).Kind().String() {
return nil, toFail(like)
}
switch c.ify {
case "bool":
if !out[ify].Bool() {
return nil, toFail(like)
}
case "error":
if !out[ify].IsNil() {
return nil, out[ify].Interface().(error)
}
}
return out[0].Interface(), nil
}
// 队列
var out []reflect.Value
pos := 0
for _, key := range c.queue {
in := []reflect.Value{}
fn := p.m[key]
end := pos + len(fn.args) - len(out)
for _, arg := range out {
in = append(in, proto.ValueOf(arg))
}
for _, arg := range args[pos:end] {
in = append(in, proto.ValueOf(arg))
}
pos = end
out = fn.apply.Call(in)
end = len(out) - 1
if end < 0 {
return nil, toFail(like)
}
switch fn.ify {
case "bool":
if out[end].Kind() != reflect.Bool || !out[end].Bool() {
return nil, toFail(like)
}
out = out[:end]
case "error":
if !out[end].IsNil() {
return nil, out[end].Interface().(error)
}
out = out[:end]
}
}
return out[0].Interface(), nil
}