When people have the “which IDE is best” argument, what they’re actually discussing is “which slightly souped-up monospace text editor with a build button do you like using”. Eclipse, Xcode, IntelliJ, Visual Studio…all of these tools riff on the same design—letting you see the source code and change the source code. As secondary effects you can also do things like build the source code, run the built product, and debug it.
The most successful IDE in the world, I would contend (and then wave my hands unconvincingly when anyone asks for data), is one that’s not designed like that at all. It’s the one that is used by more non-software specialists than any of those named above. The one that doesn’t require you to practice being an IDE user for years before you get any good. The one that business analysts, office assistants, accountants and project managers alike all turn to when they need their computer to run through some custom algorithm.
The IDE whose name appears in the title of this post.
Now what makes a spreadsheet better as a development environment is difficult to say; I’m unaware of anyone having researched it. But what makes it a different development environment from an IDE can be clearly seen by using each of them.
In a spreadsheet, it’s the inputs and results that are front-and-centre in the presentation, not the intermediate stuff that gets you from one to the other. You can test your “code” by typing in a different input and watching the results change in front of you. You can see intermediate results, not by breaking and stepping through, or putting in a log statement then switching to the log view, but by breaking the algorithm up into smaller steps (or functions or procedures, if you want to call them that). You can then visualise how these intermediate results change right along side the inputs and outputs. That’s quicker feedback than even REPLs can offer.
Many spreadsheet users naturally adopt a “test-first” approach; they create inputs for which they know what the results should be and make successively better attempts to build a formula that achieves these results. And, of course, interesting visualisations like graphs are available (though the quality does vary between products). Drawing a graph in Xcode is…challenging (and yes, nerds, I know about CorePlot).
All of this is not to say that spreadsheets are the future of IDEs. In many ways spreadsheets are more accessible as IDEs, and it’d be good to study and learn from the differences and incorporate some of them into the things that are the future of IDEs.