38 lines
619 B
Go
38 lines
619 B
Go
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// iterator.go
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package expr
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import "io"
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type Iterator interface {
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Reset()
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Next() (item any, err error) // must return io.EOF after the last item
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Index() int
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}
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type FlatArrayIterator struct {
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a []any
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index int
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}
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func NewFlatArrayIterator(array []any) *FlatArrayIterator {
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return &FlatArrayIterator{a: array, index: 0}
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}
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func (it *FlatArrayIterator) Reset() {
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it.index = 0
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}
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func (it *FlatArrayIterator) Next() (item any, err error) {
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if it.index < len(it.a) {
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item = it.a[it.index]
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it.index++
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} else {
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err = io.EOF
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}
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return
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}
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func (it *FlatArrayIterator) Index() int {
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return it.index - 1
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}
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