Go Console Output Functions: Println, Print, and Printf

Print, Println, and Printf

fmt.Print() prints its arguments as strings.
fmt.Println() inserts spaces between arguments and prints a newline character (\n) at the end.
fmt.Printf() prints arguments using format specifiers such as %d for numbers and %s for strings.

package main

import "fmt"

func main() {
    num := 123
    str := "ABC"

    fmt.Print("num=", num, " str=", str, "\n")  // no automatic newline, spaces, or formatting
    fmt.Println("num =", num, "str =", str )    // automatic newline and spaces, no formatting
    fmt.Printf("num=%d str=%s\n", num, str)     // no automatic newline or spaces, with formatting
}

num=123 str=ABC
num = 123 str = ABC
num=123 str=ABC

The following format specifiers can be used with Printf(). %4d prints a four-character integer, and %04d prints a four-character integer padded with zeros.

%v  default format
%#v Go syntax representation that shows the type structure
%t  bool
%d  integer in decimal notation
%s  string
%c  character
%f  fixed-point number
%F  fixed-point number
%e  floating-point number with e
%E  floating-point number with E
%g  compact floating-point representation; automatically selects %f or %e
%G  compact floating-point representation
%b  binary
%o  octal
%O  octal including the 0o prefix
%x  hexadecimal with lowercase letters (a-f)
%X  hexadecimal with uppercase letters (A-F)
%U  Unicode
%p  pointer
%q  quoted "..." string
%T  type
%%  percent sign