math/big: add examples for Rat and Int's SetString and Scan methods
R=golang-dev, bradfitz, rsc, r, gri, r
CC=golang-dev
https://golang.org/cl/5543047
diff --git a/src/pkg/math/big/example_test.go b/src/pkg/math/big/example_test.go
new file mode 100644
index 0000000..ba676ec
--- /dev/null
+++ b/src/pkg/math/big/example_test.go
@@ -0,0 +1,51 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package big_test
+
+import (
+ "fmt"
+ "log"
+ "math/big"
+)
+
+// 3.142
+func ExampleRat_SetString() {
+ r := new(big.Rat)
+ r.SetString("355/113")
+ fmt.Println(r.FloatString(3))
+}
+
+// 420
+func ExampleInt_SetString() {
+ i := new(big.Int)
+ i.SetString("644", 8) // octal
+ fmt.Println(i)
+}
+
+// 3/2
+func ExampleRat_Scan() {
+ // The Scan function is rarely used directly;
+ // the fmt package recognizes it as an implementation of fmt.Scanner.
+ r := new(big.Rat)
+ _, err := fmt.Sscan("1.5000", r)
+ if err != nil {
+ log.Println("error scanning value:", err)
+ } else {
+ fmt.Println(r)
+ }
+}
+
+// 18446744073709551617
+func ExampleInt_Scan() {
+ // The Scan function is rarely used directly;
+ // the fmt package recognizes it as an implementation of fmt.Scanner.
+ i := new(big.Int)
+ _, err := fmt.Sscan("18446744073709551617", i)
+ if err != nil {
+ log.Println("error scanning value:", err)
+ } else {
+ fmt.Println(i)
+ }
+}
