[Jtsummers]

Yes, you can mix and match the two. This lets you do things like build a library with SPARK for some critical portion where you want SPARK's guarantees and can accept its limitations, and incorporate it into an application built with the rest of Ada.

[lenkite]

Oh lovely - need to put Ada on the learning plan. Formal languages were a bit of a drag because you needed to maintain a separate "specification" copy of your critical code.

Going through Ada sample programs and surprised I can grok stuff without knowing anything about the language. Wondering why it never took off in the standard software world. Sure its a bit verbose, but so are Java and MacOS API's

[Agingcoder]

I think at least slow and expensive compilers back in the days, the defense and aerospace stigma, and in more recent times a common misperception that it’s closed source. And it’s never been cool stuff.

And yes you’re right, it’s a very good language.

[Jtsummers]

https://learn.adacore.com/ - I'd start here, good set of tutorials on the language including some comparative ones. It won't teach you everything you might need to know, but it's a free and good starting point.