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: main.go
    path of file: ./repos/rust-brotli/c/go
    
    the code of the file until where you have to start completion: package main

import (
	"github.com/dropbox/rust-brotli/c/go/brotli"
	"io"
	"io/ioutil"
	"os"
)

func main() {
	decompress := false
	options := brotli.CompressionOptions{
		NumThreads: 1,
		Quality:    9.5,
		Catable:    true,
		Appendable: true,
		Magic:      false,
	}
	useWriter :
    
func main() {
	decompress := false
	options := brotli.CompressionOptions{
		NumThreads: 1,
		Quality:    9.5,
		Catable:    true,
		Appendable: true,
		Magic:      false,
	}
	useWriter := false
	var toCat []string
	for index, arg := range os.Args {
		if index == 0 {
			continue
		}
		if arg == "-w" {
			useWriter = true
		}
		if arg == "-d" {
			decompress = true
		}
		if arg == "-dirtree" {
			recursiveVerify(os.Args[index+1])
			return
		}
		if arg == "-cat" {
			toCat = append(toCat, os.Args[index+1:]...)
			break
		}
	}
	if toCat != nil {
		if useWriter {
			buffers := make([][]byte, len(toCat))
			for index, fn := range toCat {
				var err error
				buffers[index], err = ioutil.ReadFile(fn)
				if err != nil {
					panic(err)
				}
			}
			final, err := brotli.BroccoliConcat(buffers...)
			if err != nil {
				panic(err)
			}
			_, err = os.Stdout.Write(final)
			if err != nil {
				panic(err)
			}
		} else {
			files := make([]io.Reader, len(toCat))
			for index, fn := range toCat {
				var err error
				files[index], err = os.Open(fn)
				if err != nil {
					panic(err)
				}
			}
			_, err := io.Copy(os.Stdout, brotli.NewBroccoliConcatReader(files...))
			if err != nil {
				panic(err)
			}
			for _, file := range files {
				if readCloser, ok := file.(io.ReadCloser); ok {
					_ = readCloser.Close()
				}
			}
		}
		return
	} else if useWriter {
		var writer io.Writer
		if decompress {
			writer = brotli.NewDecompressionWriter(
				os.Stdout,
			)
		} else {
			if options.NumThreads == 1 {
				writer = brotli.NewCompressionWriter(
					os.Stdout,
					options,
				)
			} else {
				writer = brotli.NewMultiCompressionWriter(
					os.Stdout,
					options,
				)
			}
		}
		for {
			var buffer [65536]byte
			count, err := os.Stdin.Read(buffer[:])
			if err == io.EOF {
				break
			}
			if err != nil {
				panic(err)
			}
			_, err = writer.Write(buffer[:count])
			if err != nil {
				panic(err)
			}
		}
		if writeCloser, ok := writer.(io.WriteCloser); ok {
			err := writeCloser.Close()
			if err != nil {
				panic(err)
			}
		}
	} else {
		var reader io.Reader
		if decompress {
			reader = brotli.NewDecompressionReader(
				os.Stdin,
			)
		} else {
			if options.NumThreads == 1 {
				reader = brotli.NewCompressionReader(
					os.Stdin,
					options,
				)
			} else {
				reader = brotli.NewMultiCompressionReader(
					os.Stdin,
					options,
				)
			}
		}
		for {
			var buffer [65536]byte
			size, err := reader.Read(buffer[:])
			_, werr := os.Stdout.Write(buffer[:size])
			if werr != nil {
				panic(werr)
			}
			if err == io.EOF {
				return
			}
			if err != nil {
				panic(err)
			}
		}
	}
}