I've never been able to remember the arguments for
Array#reduce. Every time I think I've managed to do it I just get it wrong.
Luckily for me, Ruby has very good documentation on its standard library and, what's even better, it ships with a CLI to explore it so I don't even need to Google it 😬
It has a very good interactive mode as well (
ri -i) In which you can search whatever you want :)
Oh, and if you use Vim you can access it by using
K over any word. Check this out: