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: lexer.go
    path of file: ./repos/plumber/vendor/github.com/graph-gophers/graphql-go/internal/common
    
    the code of the file until where you have to start completion: package common

import (
	"bytes"
	"fmt"
	"strconv"
	"strings"
	"text/scanner"

	"github.com/graph-gophers/graphql-go/errors"
	"github.com/graph-gophers/graphql-go/types"
)

type syntaxError string

type Lexer struct {
	sc                    *scanner.Scanner
	next              
    
func (l *Lexer) consumeComment() {
	if l.next != '#' {
		panic("consumeComment used in wrong context")
	}

	// TODO: count and trim whitespace so we can dedent any following lines.
	if l.sc.Peek() == ' ' {
		l.sc.Next()
	}

	if l.comment.Len() > 0 {
		l.comment.WriteRune('\n')
	}

	for {
		next := l.sc.Next()
		if next == '\r' || next == '\n' || next == scanner.EOF {
			break
		}
		l.comment.WriteRune(next)
	}
}