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/ddosify/core/scenario/scripting/assertion/lexer
    
    the code of the file until where you have to start completion: package lexer

import (
	"strings"

	"go.ddosify.com/ddosify/core/scenario/scripting/assertion/token"
)

type Lexer struct {
	input        string
	position     int  // current position in input (points to current char)
	readPosition int  // current reading position in input (after current char)
	ch           byte // current char under examination
}

func New(input string) *Lexer {
	l := &Lexer{input: input}
	l.readChar()
	return l
}

func (l *Lexer) NextToken() token.Token {
	var tok token.Token

	l.skipWhitespace()

	switch l.ch {
	case '=':
		if l.peekChar() == '=' {
			ch := l.ch
			l.readChar()
			literal := string(ch) + string(l.ch)
			tok = token.Token{Type: token.EQ, Literal: literal}
		} else {
			tok = newToken(token.ILLEGAL, l.ch)
		}
	case '&':
		if l.peekChar() == '&' {
			ch := l.ch
			l.readChar()
			literal := string(ch) + string(l.ch)
			tok = token.Token{Type: token.AND, Literal: literal}
		} else {
			tok = newToken(token.ILLEGAL, l.ch)
		}
	case '|':
		if l.peekChar() == '|' {
			ch := l.ch
			l.readChar()
			literal := string(ch) + string(l.ch)
			tok = token.Token{Type: token.OR, Literal: literal}
		} else {
			tok = newToken(token.ILLEGAL, l.ch)
		}
	case '+':
		tok = newTok
    
func (l *Lexer) NextToken() token.Token {
	var tok token.Token

	l.skipWhitespace()

	switch l.ch {
	case '=':
		if l.peekChar() == '=' {
			ch := l.ch
			l.readChar()
			literal := string(ch) + string(l.ch)
			tok = token.Token{Type: token.EQ, Literal: literal}
		} else {
			tok = newToken(token.ILLEGAL, l.ch)
		}
	case '&':
		if l.peekChar() == '&' {
			ch := l.ch
			l.readChar()
			literal := string(ch) + string(l.ch)
			tok = token.Token{Type: token.AND, Literal: literal}
		} else {
			tok = newToken(token.ILLEGAL, l.ch)
		}
	case '|':
		if l.peekChar() == '|' {
			ch := l.ch
			l.readChar()
			literal := string(ch) + string(l.ch)
			tok = token.Token{Type: token.OR, Literal: literal}
		} else {
			tok = newToken(token.ILLEGAL, l.ch)
		}
	case '+':
		tok = newToken(token.PLUS, l.ch)
	case '-':
		tok = newToken(token.MINUS, l.ch)
	case '!':
		if l.peekChar() == '=' {
			ch := l.ch
			l.readChar()
			literal := string(ch) + string(l.ch)
			tok = token.Token{Type: token.NOT_EQ, Literal: literal}
		} else {
			tok = newToken(token.BANG, l.ch)
		}
	case '/':
		tok = newToken(token.SLASH, l.ch)
	case '*':
		tok = newToken(token.ASTERISK, l.ch)
	case '<':
		tok = newToken(token.LT, l.ch)
	case '>':
		tok = newToken(token.GT, l.ch)
	case ',':
		tok = newToken(token.COMMA, l.ch)
	case '(':
		tok = newToken(token.LPAREN, l.ch)
	case ')':
		tok = newToken(token.RPAREN, l.ch)
	case '{':
		tok = newToken(token.LBRACE, l.ch)
	case '}':
		tok = newToken(token.RBRACE, l.ch)
	case '[':
		tok = newToken(token.LBRACKET, l.ch)
	case ']':
		tok = newToken(token.RBRACKET, l.ch)
	case ':':
		tok = newToken(token.COLON, l.ch)
	case 0:
		tok.Literal = ""
		tok.Type = token.EOF
	default:
		if l.ch == 34 { // "
			l.readChar()
			tok.Literal = l.readString()
			tok.Type = token.STRING
			l.readChar()
			return tok
		}
		if l.ch == 39 { // '
			l.readChar()
			tok.Literal = l.readRawString()
			tok.Type = token.STRING
			l.readChar()
			return tok
		}
		if isDigit(l.ch) { // number
			tok.Type = token.INT
			tok.Literal = l.readNumber()
			if strings.Contains(tok.Literal, ".") {
				if strings.Count(tok.Literal, ".") > 1 { // more than 1 . is illegal
					tok.Type = token.ILLEGAL
				}
				tok.Type = token.FLOAT
			} else {
				tok.Type = token.INT
			}
			return tok
		} else if isLetter(l.ch) { // identifier
			tok.Literal = l.readIdentifier()
			tok.Type = token.LookupIdent(tok.Literal)
			return tok
		} else {
			tok = newToken(token.ILLEGAL, l.ch)
		}
	}

	l.readChar()
	return tok
}