bytes.Buffer equivalent in JS

[pgundlach]

I have a struct with a bytes.Buffer entry. How would I access this on the Javascript side? If this is not accessible: what would be an alternative approach without changing the struct within document? Should I create a wrapper structure / method and assign the values to the Field entry? Is there a way to add a function to the document object on the JS side?

package main

import (
	"bytes"
	"fmt"
	"os"

	"github.com/dop251/goja"
)

type document struct {
	Field bytes.Buffer
}

func newDocument() *document {
	d := &document{}
	// I'd like to have this on the javascript side:
	// d.Field.Write([]byte("foo"))
	return d
}

func (d *document) Check() {
	// Goal: should print "foo"
	fmt.Println(`~~> d.Field`, d.Field.String())
}

func main() {
	runtime := goja.New()

	gjNewDoc := func(call goja.FunctionCall) goja.Value {
		return runtime.ToValue(newDocument())
	}
	runtime.Set("newdoc", gjNewDoc)

	_, err := runtime.RunString(`
var d = newdoc();
d.Field = "foo";
d.Check();
`)
	if err != nil {
		fmt.Println(err)
		os.Exit(-1)
	}

}

[dop251]

Just replace

d.Field = "foo";

with

d.Field.Write("foo")

[pgundlach]

This is so obvious and I feel so dumb. Thank you very much.