move: log parser

interfaces/log-parser/oop/groupers.go

@@ -0,0 +1,15 @@
+package main
+
+type groupFunc func(result) string
+
+// domainGrouper groups by domain.
+// but it keeps the other fields.
+// for example: it returns pages as well, but you shouldn't use them.
+// exercise: write a function that erases the unnecessary data.
+func domainGrouper(r result) string {
+	return r.domain
+}
+
+func pageGrouper(r result) string {
+	return r.domain + r.page
+}