From 28903ad6c86247eb872076bb0925aa1d904b706b Mon Sep 17 00:00:00 2001
From: Inanc Gumus <m@inanc.io>
Date: Sat, 27 Apr 2019 10:45:47 +0300
Subject: [PATCH] add: error handling to scanner example

---
 23-project-log-parser/01-scanning/main.go                | 9 +++++++++
 23-project-log-parser/02-project-log-parser/main.go      | 5 +++++
 24-structs/05-project-log-parser-structs/main.go         | 5 +++++
 25-functions-and-pointers/03-refactor-to-funcs/main.go   | 5 +++++
 .../04-pass-by-value-semantics/main.go                   | 5 +++++
 25-functions-and-pointers/08-log-parser-pointers/main.go | 6 +++++-
 x-tba/log-parser-json/main.go                            | 4 ++++
 7 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/23-project-log-parser/01-scanning/main.go b/23-project-log-parser/01-scanning/main.go
index 187ecbd..0f49476 100644
--- a/23-project-log-parser/01-scanning/main.go
+++ b/23-project-log-parser/01-scanning/main.go
@@ -17,6 +17,9 @@ func main() {
 	// Create a new scanner that scans from the standard-input
 	in := bufio.NewScanner(os.Stdin)
 
+	// Simulate an error
+	// os.Stdin.Close()
+
 	// Stores the total number of lines in the input
 	var lines int
 
@@ -27,6 +30,12 @@ func main() {
 		// Get the current line from the scanner's buffer
 		// fmt.Println("Scanned Text :", in.Text())
 		// fmt.Println("Scanned Bytes:", in.Bytes())
+		in.Text()
 	}
 	fmt.Printf("There %d lines.\n", lines)
+
+	err := in.Err()
+	if err != nil {
+		fmt.Println("ERROR:", err)
+	}
 }
diff --git a/23-project-log-parser/02-project-log-parser/main.go b/23-project-log-parser/02-project-log-parser/main.go
index 5ffc2d4..1fb6738 100644
--- a/23-project-log-parser/02-project-log-parser/main.go
+++ b/23-project-log-parser/02-project-log-parser/main.go
@@ -70,4 +70,9 @@ func main() {
 
 	// Print the total visits for all domains
 	fmt.Printf("\n%-30s %10d\n", "TOTAL", total)
+
+	// Let's handle the error
+	if err := in.Err(); err != nil {
+		fmt.Println("> Err:", err)
+	}
 }
diff --git a/24-structs/05-project-log-parser-structs/main.go b/24-structs/05-project-log-parser-structs/main.go
index cd3394f..b744ad4 100644
--- a/24-structs/05-project-log-parser-structs/main.go
+++ b/24-structs/05-project-log-parser-structs/main.go
@@ -86,4 +86,9 @@ func main() {
 
 	// Print the total visits for all domains
 	fmt.Printf("\n%-30s %10d\n", "TOTAL", p.total)
+
+	// Let's handle the error
+	if err := in.Err(); err != nil {
+		fmt.Println("> Err:", err)
+	}
 }
diff --git a/25-functions-and-pointers/03-refactor-to-funcs/main.go b/25-functions-and-pointers/03-refactor-to-funcs/main.go
index a669711..00ca604 100644
--- a/25-functions-and-pointers/03-refactor-to-funcs/main.go
+++ b/25-functions-and-pointers/03-refactor-to-funcs/main.go
@@ -59,4 +59,9 @@ func main() {
 
 	// Print the total visits for all domains
 	fmt.Printf("\n%-30s %10d\n", "TOTAL", p.total)
+
+	// Let's handle the error
+	if err := in.Err(); err != nil {
+		fmt.Println("> Err:", err)
+	}
 }
diff --git a/25-functions-and-pointers/04-pass-by-value-semantics/main.go b/25-functions-and-pointers/04-pass-by-value-semantics/main.go
index d63490d..7f1e1fe 100644
--- a/25-functions-and-pointers/04-pass-by-value-semantics/main.go
+++ b/25-functions-and-pointers/04-pass-by-value-semantics/main.go
@@ -45,4 +45,9 @@ func main() {
 
 	// Print the total visits for all domains
 	fmt.Printf("\n%-30s %10d\n", "TOTAL", p.total)
+
+	// Let's handle the error
+	if err := in.Err(); err != nil {
+		fmt.Println("> Err:", err)
+	}
 }
diff --git a/25-functions-and-pointers/08-log-parser-pointers/main.go b/25-functions-and-pointers/08-log-parser-pointers/main.go
index f24d393..a07dfb3 100644
--- a/25-functions-and-pointers/08-log-parser-pointers/main.go
+++ b/25-functions-and-pointers/08-log-parser-pointers/main.go
@@ -31,6 +31,10 @@ func main() {
 	fmt.Printf("\n%-25s -> %d\n", "TOTAL", p.total)
 
 	if p.lerr != nil {
-		fmt.Printf("> Err: %s\n", p.lerr)
+		fmt.Println("> Err:", p.lerr)
+	}
+
+	if err := in.Err(); err != nil {
+		fmt.Println("> Err:", err)
 	}
 }
diff --git a/x-tba/log-parser-json/main.go b/x-tba/log-parser-json/main.go
index b85b8a8..903cf83 100644
--- a/x-tba/log-parser-json/main.go
+++ b/x-tba/log-parser-json/main.go
@@ -88,6 +88,10 @@ func main() {
 	// // Print the total visits for all domains
 	// fmt.Printf("\n%-30s %10d\n", "TOTAL", p.Total)
 
+	// if err := in.Err(); err != nil {
+	// 	fmt.Println("> Err:", err)
+	// }
+
 	s, _ := json.MarshalIndent(p, "", "\t")
 	fmt.Println(string(s))
 }