[glass_of_water]

If that were true, text books wouldn't contain any diagrams. So I think it's fairly uncontroversial to say that there are cases when text is not the best way to incept ideas. So why should we be confined to just text when writing code? Should we not be free to choose the best tool for the job?

[dotopotoro]

You should check out IDEs :)

IDE takes plain old text as input, and lets the coder to interact with the model of the program.

1. Various graphical hints in text (highlighting keywords, selections, …)

2. Visualisation tools (draw database and class diagrams)

3. Navigation capabilities (go to implementation, definition etc)

4. Refactoring capabilities (“rename, “extract variable”, …)

In my view, IDE is already “book with diagrams”. (“Diagrams” can still be improved, but concept is really there)

[panstromek]

True, but IDEs are currently severely limited by nature of textual sources (e.g. macros are notoriously tricky to deal with). It's much easier to start from a good model for IDE and derive textual reprentation and input method from that.

[preseinger]

No, it is not the case that if the thing I said was true, then textbooks wouldn't contain diagrams.

[samatman]

If GPs statement were true, textbooks would be called text books instead of diagram books.