Hands-On High Performance with Go

Default functions

Sprig's default functions return default values for templated functions. We can check the default values for particular data structures and whether or not they are empty. Empty is defined for each data type:

Numeric	0
String	"" (empty string)
Lists	[] (empty list)
Dicts	{} (empty dict)
Boolean	false
And always	Nil (also referred to as null)
Structs	No definition for empty; will never return the default

We start with our imports:

package main        import (    "fmt"    "os"    "text/template"            "github.com/Masterminds/sprig")         

Next, we set up our empty and non-empty template variables:

func main() {            emptyTemplate := map[string]interface{}{"Name": ""}  fullTemplate := map[string]interface{}{"Name": "Bob"} ...