You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mime.go
    path of file: ./repos/fyne/internal/repository/mime
    
    the code of the file until where you have to start completion: package mime

import "strings"

// Split spits the mimetype into its main type and subtype.
func Split(mimeTypeFull string) (mimeType, mimeSubType string) {
	// Replace with strings.Cut() when Go 1.18 is our new base version.
	separatorIndex := strings.IndexByte(mimeTypeFull, '/')
	if separatorIndex == -1 ||
    
func Split(mimeTypeFull string) (mimeType, mimeSubType string) {
	// Replace with strings.Cut() when Go 1.18 is our new base version.
	separatorIndex := strings.IndexByte(mimeTypeFull, '/')
	if separatorIndex == -1 || mimeTypeFull[separatorIndex+1:] == "" {
		return "", "" // Empty or only one part. Ignore.
	}

	mimeType = mimeTypeFull[:separatorIndex]
	mimeSubType = mimeTypeFull[separatorIndex+1:]
	return
}