| // run |
| |
| // Copyright 2022 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package main |
| |
| type TaskInput interface { |
| deps() []*taskDefinition |
| } |
| |
| type Value[T any] interface { |
| metaValue |
| } |
| |
| type metaValue interface { |
| TaskInput |
| } |
| |
| type taskDefinition struct { |
| } |
| |
| type taskResult struct { |
| task *taskDefinition |
| } |
| |
| func (tr *taskResult) deps() []*taskDefinition { |
| return nil |
| } |
| |
| func use[T any](v Value[T]) { |
| _, ok := v.(*taskResult) |
| if !ok { |
| panic("output must be *taskResult") |
| } |
| } |
| |
| func main() { |
| tr := &taskResult{&taskDefinition{}} |
| use[string](Value[string](tr)) |
| } |
