28 lines
458 B
Go
28 lines
458 B
Go
package locker
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import "context"
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type Locked[T any] struct {
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state chan *T
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}
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func New[T any](initial *T) *Locked[T] {
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s := &Locked[T]{}
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s.state = make(chan *T, 1)
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s.state <- initial
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return s
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}
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func (s *Locked[T]) Modify(ctx context.Context, fn func(*T) error) error {
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if ctx.Err() != nil {
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return ctx.Err()
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}
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select {
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case state := <-s.state:
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defer func() { s.state <- state }()
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return fn(state)
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case <-ctx.Done():
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return ctx.Err()
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}
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} |