add: new interfaces

interfaces/functional/textreader.go

@@ -0,0 +1,39 @@
+// 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 (
+	"bufio"
+	"fmt"
+	"io"
+)
+
+func textReader(r io.Reader) inputFn {
+	return func(process processFn) error {
+		var (
+			l  = 1
+			in = bufio.NewScanner(r)
+		)
+
+		for in.Scan() {
+			r, err := fastParseFields(in.Bytes())
+			// r, err := parseFields(in.Text())
+			if err != nil {
+				return fmt.Errorf("line %d: %v", l, err)
+			}
+
+			process(r)
+			l++
+		}
+
+		if c, ok := r.(io.Closer); ok {
+			c.Close()
+		}
+		return in.Err()
+	}
+}