func NewDispenserTokens(filename string, tokens []Token) Dispenser {
	return Dispenser{
		filename: filename,
		tokens:   tokens,
		cursor:   -1,
	}
}
NewDispenserTokens returns a Dispenser filled with the given tokens.
package casketfile
import (
	"errors"
	"fmt"
	"io"
	"strings"
)
type Dispenser struct {
	filename string
	tokens   []Token
	cursor   int
	nesting  int
}
func NewDispenser(filename string, input io.Reader) Dispenser {
	tokens, _ := allTokens(input)  
	return Dispenser{
		filename: filename,
		tokens:   tokens,
		cursor:   -1,
	}
}