package main
 
import (
 "reflect"
)
 
type TryCatch struct {
 errChan  chan interface{}
 catches  map[reflect.Type]func(err error)
 defaultCatch func(err error)
}
 
func (t TryCatch) Try(block func()) TryCatch {
 t.errChan = make(chan interface{})
 t.catches = map[reflect.Type]func(err error){}
 t.defaultCatch = func(err error) {}
 go func() {
 defer func() {
 t.errChan <- recover()
 }()
 block()
 }()
 return t
}
 
func (t TryCatch) CatchAll(block func(err error)) TryCatch {
 t.defaultCatch = block
 return t
}
 
func (t TryCatch) Catch(e error, block func(err error)) TryCatch {
 errorType := reflect.TypeOf(e)
 t.catches[errorType] = block
 return t
}
 
func (t TryCatch) Finally(block func()) TryCatch {
 err := <-t.errChan
 if err != nil {
 catch := t.catches[reflect.TypeOf(err)]
 if catch != nil {
 catch(err.(error))
 } else {
 t.defaultCatch(err.(error))
 }
 }
 block()
 return t
}
 
type MyError struct {
 error
}
 
func main() {
 TryCatch{}.Try(func() {
 println("do something buggy")
 panic(MyError{})
 }).Catch(MyError{}, func(err error) {
 println("catch MyError")
 }).CatchAll(func(err error) {
 println("catch error")
 }).Finally(func() {
 println("finally do something")
 })
 println("done")
}