Multiple source files, directory structures and namespaces in functional programming

I was surprised to see that the source code for Hacker News is just one big file containing a fl开发者_开发问答at list of function definitions.

hacker news algorithm in php?

This is the Hacker News ranking algorithm, which I think is a simple way of ranking things, espcially if users are voting on items, but I really dnt understand this, can this be converted to PHP, so I

紧紧把我抱住是什么歌？