> Not so long ago I read a history here in HN about a guy that first coded in his head, then wrote everything in paper, and finally coded in a computer. It compiled without errors. Slow pusher? Inefficient?

I've read and heard stories about these folks too, apparently this was more common decades ago.

To be clear, I don't think I could pull it off with any language. It's quite impressive and admirable to get things right on the first try.

Having said that, the thing is, languages were a lot simpler back then too. I'm not convinced this is realistically even possible with today's languages unless you constrain yourself to some overly restrictive subset. Like try this with C++, and I would be shocked if you can write nontrivial programs without getting compiler errors. Like to give a trivial example, every time I write my own iterator class for a container, I miss something when I hit compile: like either a comparison operator, or subtraction, or conversion to const iterator, or post-decrement, or subscript, or some member typedef. Or try it with python, and I bet you'll call .get() on something and then forget to check for null somewhere.

I would love to be proven wrong though. If anyone knows of someone who does this with a modern language, please share.

They invented .gitignore to prevent those files to get checked in into the repository.

Head, paper, keyboard is what we did in the 80s when compilers were too slow to afford throwing code at them and fix the errors later. Was that code in the HN story a substantial piece of code or some 100 lines program? Our programs used to be small.