Carrying on with the crawler's implementation

So far, your code should look like this:

using HTTP, Gumbo 

const PAGE_URL = "https://en.wikipedia.org/wiki/Julia_(programming_language)" 
const LINKS = String[] 

function fetchpage(url) 
  response = HTTP.get(url) 
  if response.status == 200 && parse(Int, Dict(response.headers)["Content-Length"]) > 0 
    String(response.body) 
  else 
    "" 
  end 
end 

It should be now clear that either the response body or an empty string is returned by the if/else statement. And since this is the last piece of code evaluated inside the fetchpage function, this value also becomes the return value of the whole function.

All good, we can now use the fetchpage function to get the HTML content of the Wikipedia page and store it in the content variable:

content = fetchpage(PAGE_URL)  

If the fetch operation...