34 lines
604 B
Go
34 lines
604 B
Go
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// For more tutorials: https://blog.learngoprogramming.com
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//
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// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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package main
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import "fmt"
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// logCount counts the yielded records
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type logCount struct {
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iterator
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n int
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}
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func (lc *logCount) each(yield resultFn) error {
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err := lc.iterator.each(func(r result) {
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lc.n++
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yield(r)
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})
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if err != nil {
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// lc.n+1: iterator.each won't call yield on err
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return fmt.Errorf("record %d: %v", lc.n+1, err)
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}
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return nil
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}
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func (lc *logCount) count() int {
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return lc.n
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}
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