70 lines
1.1 KiB
Go
70 lines
1.1 KiB
Go
package iter
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import (
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"sync"
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"github.com/anacrolix/missinggo"
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)
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type Iterable interface {
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Iter(Callback)
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}
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type iterator struct {
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it Iterable
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ch chan interface{}
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value interface{}
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ok bool
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mu sync.Mutex
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stopped missinggo.Event
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}
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func NewIterator(it Iterable) (ret *iterator) {
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ret = &iterator{
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it: it,
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ch: make(chan interface{}),
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}
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go func() {
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// Have to do this in a goroutine, because the interface is synchronous.
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it.Iter(func(value interface{}) bool {
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select {
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case ret.ch <- value:
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return true
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case <-ret.stopped.LockedChan(&ret.mu):
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return false
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}
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})
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close(ret.ch)
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ret.mu.Lock()
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ret.stopped.Set()
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ret.mu.Unlock()
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}()
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return
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}
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func (me *iterator) Value() interface{} {
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if !me.ok {
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panic("no value")
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}
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return me.value
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}
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func (me *iterator) Next() bool {
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me.value, me.ok = <-me.ch
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return me.ok
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}
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func (me *iterator) Stop() {
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me.mu.Lock()
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me.stopped.Set()
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me.mu.Unlock()
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}
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func IterableAsSlice(it Iterable) (ret []interface{}) {
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it.Iter(func(value interface{}) bool {
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ret = append(ret, value)
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return true
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})
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return
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}
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