How to pretty print variables
GoPretty PrintGo Problem Overview
Is there something like Ruby's awesome_print
in Go?
For example in Ruby you could write:
require 'ap'
x = {a:1,b:2} // also works for class
ap x
the output would be:
{
"a" => 1,
"b" => 2
}
closest thing that I could found is Printf("%#v", x)
Go Solutions
Solution 1 - Go
If your goal is to avoid importing a third-party package, your other option is to use json.MarshalIndent:
x := map[string]interface{}{"a": 1, "b": 2}
b, err := json.MarshalIndent(x, "", " ")
if err != nil {
fmt.Println("error:", err)
}
fmt.Print(string(b))
Output:
{
"a": 1,
"b": 2
}
Working sample: http://play.golang.org/p/SNdn7DsBjy
Solution 2 - Go
Nevermind, I found one: https://github.com/davecgh/go-spew
// import "github.com/davecgh/go-spew/spew"
x := map[string]interface{}{"a":1,"b":2}
spew.Dump(x)
Would give an output:
(map[string]interface {}) (len=2) {
(string) (len=1) "a": (int) 1,
(string) (len=1) "b": (int) 2
}
Solution 3 - Go
If you want pretty coloured output, you can use pp
.
import "github.com/k0kubun/pp"
...
pp.Print(m)
Solution 4 - Go
I came up to use snippet like this:
func printMap(m map[string]string) {
var maxLenKey int
for k, _ := range m {
if len(k) > maxLenKey {
maxLenKey = len(k)
}
}
for k, v := range m {
fmt.Println(k + ": " + strings.Repeat(" ", maxLenKey - len(k)) + v)
}
}
The output will be like this:
short_key: value1
really_long_key: value2
Tell me, if there's some simpler way to do the same alignment.
Solution 5 - Go
I just wrote a simple function based on Simons answer:
func dump(data interface{}){
b,_:=json.MarshalIndent(data, "", " ")
fmt.Print(string(b))
}