diff options
| -rw-r--r-- | go.html.markdown | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/go.html.markdown b/go.html.markdown index 7b007bab..f097caeb 100644 --- a/go.html.markdown +++ b/go.html.markdown @@ -11,6 +11,7 @@ contributors: - ["Jose Donizetti", "https://github.com/josedonizetti"] - ["Alexej Friesen", "https://github.com/heyalexej"] - ["Clayton Walker", "https://github.com/cwalk"] + - ["Leonid Shevtsov", "https://github.com/leonid-shevtsov"] --- Go was created out of the need to get work done. It's not the latest trend @@ -39,6 +40,7 @@ import ( "io/ioutil" // Implements some I/O utility functions. m "math" // Math library with local alias m. "net/http" // Yes, a web server! + "os" // OS functions like working with the file system "strconv" // String conversions. ) @@ -133,6 +135,14 @@ can include line breaks.` // Same string type. // Unused variables are an error in Go. // The underscore lets you "use" a variable but discard its value. _, _, _, _, _, _, _, _, _, _ = str, s2, g, f, u, pi, n, a3, s4, bs + // Usually you use it to ignore one of the return values of a function + // For example, in a quick and dirty script you might ignore the + // error value returned from os.Create, and expect that the file + // will always be created. + file, _ := os.Create("output.txt") + fmt.Fprint(file, "This is how you write to a file, by the way") + file.Close() + // Output of course counts as using a variable. fmt.Println(s, c, a4, s3, d2, m) @@ -211,6 +221,10 @@ func learnFlowControl() { // for each pair in the map, print key and value fmt.Printf("key=%s, value=%d\n", key, value) } + // If you only need the value, use the underscore as the key + for _, name := range []string{"Bob", "Bill", "Joe"} { + fmt.Printf("Hello, %s\n", name) + } // As with for, := in an if statement means to declare and assign // y first, then test y > x. |