Some of us learned this approach to imperative programming from The Science of Programming by David Gries:

https://www.amazon.com/Science-Programming-Monographs-Comput...

I have been intrigued by the idea of visual coding tools for many years, but these kind of tools have always disappointed me. They remind me of the system used to teach small children to program in the programming language Scratch, see [Scratch].

I prefer to "visualize" my code as manipulating a set of logical assertions that characterize the state of the computation, ultimately reaching the point where the state of the computation's properties satisfy the requirements. Somewhat like that explained in [Gries1987] and [Dijkstra1976]. Visual tools are just too coarse to capture the details necessary to ensure correctness or real-life requirements.

While UML diagrams sometimes help to make sense of a complex set of OO Class relationships, this is far from how I normally work with the meaning of code in my head while programming.

[Scratch] https://en.wikipedia.org/wiki/Scratch_(programming_language)

[Gries1987] https://www.amazon.com/Science-Programming-Monographs-Comput...

[Dijkstra1976] https://www.amazon.com/Discipline-Programming-Edsger-W-Dijks...

5) advanced: https://www.amazon.com/Science-Programming-Monographs-Comput...

If you are tempted to dig further into these techniques there's this book:

https://www.amazon.com/Science-Programming-Monographs-Comput...

Heck, the basic methods of writing provably correct programs have been explained in plain English since at least the 70s:

https://www.amazon.com/Discipline-Programming-Edsger-W-Dijks...

https://www.amazon.com/Science-Programming-Monographs-Comput...

This is not some rocket science type verification with a dependently typed theorem prover language, it's fairly simple paper and pencil logic. It should not be hard to adapt it to Solidity specific concepts like running out of gas.

The reason these techniques are mostly ignored is that the techniques don't scale at all to large programs calling APIs with imprecise semantics (e.g. filesystem, network), and most people would rather publish imperfect software and iterate rather than spec everything up front. Well, unlike most software, contracts are not large, their semantics are meant to be 100% precise, and most people would rather take the time to make sure a contract does what it claims to do rather than discover a bug afterwards. I would hope.

@jhck, drothlis: Thank you very much to both of you, those suggestions are exactly what was asked for. I'd upvote you more if I could. :)

Both the Gries book and Stepanov's book have really impressive reviews on Amazon, am looking forward to diving into them.

http://www.amazon.com/Science-Programming-Monographs-Compute...

http://www.amazon.com/Elements-Programming-Alexander-Stepano...