I've tried it, for several languages...

It seems good, to me, but I've learned to invest in the BEST 2-ish recent books on any language I'm trying to learn:

the difference between average vs GOOD instruction is cliff-like, and I need to understand why things work the way they do.

( with 2 different-author books, best I can get, then if 1 author is explaining something in a way I can't get, then I've got a good alternative.

Better, though, is that if I make myself work through both, then it's much more likely to stick, see? : )

I consider Exercism to be a good part of a healthy ( programming-learning ) breakfast!

: )

CombinedArms: use EVERY dimension of leverage you can, simultaneously, and more-certainly win, quicker!

I'm saying this, and I also saying I've had to report bugs in their lessons, 1 or 2 times.

I need Exercism.