Welcome to another episode of the ThoughtWorks podcast.

I've attended Xconf in Hamburg, and there I met Chris Ford.

Chris Ford, why don't you start by telling our listeners who you are?

Sure.

I'm an Australian programmer, though I live in the UK now. So I've lived in London with various

trips to different parts of the world with ThoughtWorks for about six years now. And the majority of

those have been with ThoughtWorks as a tech lead. Right. And what's the topic you want to talk about?

Well, my topic was called Through the Looking Glass, which is, I guess, a little bit

of a kind of a clever play on words.

It was actually about the functional programming concept of lenses.

So I took the title of a famous book by Lewis Carroll, which is the sequel to Alice in Wonderland,

and I used that as a bit of a prop for explaining how lenses work.

And how do lenses work?

I just spent 45 minutes subscribing it now you want me to just sum it up.

I think it's quite possible.

Lenses are a way to focus from a big data structure to a particular focus inside that data

structure where you want something to happen.

So it allows you to reuse the concept of that focus and many different concepts.

So it allows you to extract something from your code that previously was probably

mixed up amongst a whole bunch of other data processing code and make it a visible

responsibility.

Okay.

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