Bjarne Stroustrup: C++ | Lex Fridman Podcast #48

The following is a conversation with Bjarne Stroustrup. He's the creator of C++, a programming language that after 40 years is still one of the most popular and powerful languages in the world. Its focus on fast, stable, robust code underlies many of the biggest systems in the world that we have come to rely on as a society. If you're watching this on YouTube, for example, many of the critical backend components of YouTube are written in C++. Same goes for Google, Facebook, Amazon, Twitter, most Microsoft applications, Adobe applications, most database systems, and most physical systems that operate in the real world, like cars, robots, rockets that launch us into space and one day will land us on Mars. C++ also happens to be the language that I use more than any other in my life. I've written several hundred thousand lines of C++ source code. Of course, lines of source code don't mean much, but they do give hints of my personal journey through the world of software. I've enjoyed watching the development of C++ as a programming language, leading up to the big update in the standard in 2011 and those that followed in '14, '17 and toward the new C++ 20 standard hopefully coming out next year. This is The Artificial Intelligence Podcast. If you enjoy it, subscribe on YouTube, give it five stars on iTunes, support it on Patreon, or simply connect with me on Twitter @lexfridman, spelled F-R-I-D-M-A-N. And now, here's my conversation with Bjarne Stroustrup. What was the first program you've ever written? Do you remember?

It was my second year in university, first year of computer science. And it was in Algol 60. I calculated the shape of a super ellipse and then connected points on the, on the perimeter, uh, creating star patterns. It was with a- w- with a wet ink on a paper printer. (laughs)

And that was in college, in university?

Yeah, yeah. I learned to program the second year in university.

And what was the first programming language, if I may ask it this way, that you fell in love with?

I, I think Algol 60. And after that, I remember... I remember SNOBOL. I remember Fortran, didn't fall in love with that. I remember Pascal, didn't fall in love with that. It all got in the way of me. Uh, and then I discovered Assembler and that was much more fun. And from there, I went to micro, um, microcode.

So you were drawn to the... You found the low-level stuff beautiful.

I, I went through a lot of languages and then I spent significant time in, in Assembler and microcode. That was sort of the first really profitable things and that paid for my master's actually. And then I discovered Simula, which was absolutely great.

Simula?

Simula was the extension of Algol 60, uh, done primarily for simulation, but basically they invented object-oriented programming and inheritance and runtime polymorphism when they were, while they were doing it. And, uh, that was a language that taught me that you could have the, sort of the problems of a program grow with size of the program rather than with the square of the size of the program. That is, you can actually modularize very nicely. And that, that, that was a surprise to me. It was also a surprise to me that a stricter type system than Pascal's was helpful, whereas Pascal's type system got in my way all the time. So you need a, a strong type system to organize your code well, but it has to be extensible and flexible.