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: gogenerate.go
    path of file: ./repos/gomacro/base/genimport
    
    the code of the file until where you have to start completion: package genimport

import (
	"fmt"
	"go/build"
	"os"
	"strings"
)

const sep = string(os.PathSeparator)

// GoGenerateMain allows gomacro to be run un
    
func GoGenerateMain(arg []string, imp *Importer) error {
	var path string
	narg := len(arg)
	switch {
	case narg == 0 || (narg > 0 && arg[0] == "."):
		cwd, err := os.Getwd()
		if err != nil {
			return fmt.Errorf("gomacro -g: error getting current dir: %v", err)
		}
		gopath := build.Default.GOPATH
		prefix := gopath + sep + "src" + sep
		if strings.HasPrefix(cwd, prefix) {
			path = cwd[len(prefix):]
		} else {
			// guess it is after the first `src` in cwd,
			// since traditionally all packages are
			// after $GOPATH/src/
			splt := strings.SplitN(cwd, sep+"src"+sep, 2)
			if len(splt) <= 1 {
				return fmt.Errorf("gomacro -g: unable to detect current package, please specify it")
			}
			path = splt[1]
		}
	default:
		path = arg[0]
		if isLocalFilesystemPath(path) {
			abspath, err := MakeAbsolutePathOrError(path)
			if err != nil {
				return err
			}
			path = abspath.String()
		}
	}
	_, err := imp.ImportPackagesOrError(
		map[string]PackageName{path: PackageName("_i")},
		true /*enableModule*/)
	return err
}