Simon Peyton Jones

A very weak one.

It doesn't even let you define new functions.

And it has a very limited collection of data types.

Namely, just, you know, flat arrays and numbers and strings.

So, when I was working for Microsoft, I took it as my war cry to say, let's take that idea.

Excel is the world's most widely used functional language by three orders of magnitude.

And, oh, it's the world's most widely used programming language by three orders of magnitude.

Not just functional language.

Excel is used by many, many more programmers, users, domain experts, than any imperative language.

Right?

Imperative language is a few million users.

Excel, hundreds of millions of users.

Right?

Even if you just restricted users who are using formulae.

So how can we delight those users?

Answer, take ideas from functional programming and use them to make Excel's formula language more powerful.

It took me 20 years, but Excel did finally add Lambda to Excel.

Look it up.

There are blog posts about it and many YouTube videos about it.

So you can now program in Excel using full Lambda as Alonzo Church originally defined it.