move: log parsers

logparser/oop/logcount.go

@@ -0,0 +1,33 @@
+// For more tutorials: https://blog.learngoprogramming.com
+//
+// Copyright © 2018 Inanc Gumus
+// Learn Go Programming Course
+// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
+//
+
+package main
+
+import "fmt"
+
+// logCount counts the yielded records
+type logCount struct {
+	iterator
+	n int
+}
+
+func (lc *logCount) each(yield recordFn) error {
+	err := lc.iterator.each(func(r record) {
+		lc.n++
+		yield(r)
+	})
+
+	if err != nil {
+		// lc.n+1: iterator.each won't call yield on err
+		return fmt.Errorf("record %d: %v", lc.n+1, err)
+	}
+	return nil
+}
+
+func (lc *logCount) count() int {
+	return lc.n
+}