EN03_Change_output

You can change the output destination by setting io.Writer in the .Writer field of the Editor structure

By default, os.Stdout is automatically set, but if it is expected to be used in an environment such as Windows where escape sequences are not enabled, an io.Writer that emulates an ANSI Escape sequence such as go-colorable can be set here. (recommended)

import (
    "github.com/mattn/go-colorable"
)
// ;

editor := &readline.Editor{
    // ;
    Writer: colorable.NewColorableStdout(),
    // ;
}

There is a similar field called .Out, which is a .Writer field buffered with bufio.Writer and set using the .ReadLine method, etc. Since this .Out is mainly used after that, changing the .Writer once it is set has no effect.