[jabkobob]

I must disagree with the command-line part. I don't think that the command line is fundamentally more powerful than any other interface.

Why is the command line powerful? Because it offers a large number of utilities that are highly configurable and that can be linked easily.

But you could have just the same expressiveness if the interface was eg. a circuit diagram, where you connect configurable commands with lines.

You know why the command line uses text input? Because it is the simplest to implement. The only people who need to know how to use the command line are people who need to use software where it doesn't pay off to make a more intuitive interface.

[thristian]

While I agree that the commandline provides "a large number of utilities" that "can be linked easily", I don't think that's the whole story. While you could certainly design a circuit-diagram-style GUI for building commands (so-called "visual programming"), it would be a lot more tedious than typing, just because there's so much more bandwidth available on a 100+ button, two-handed input device than a two-or-three button one-handed input device. Also, a good deal of efficiency comes from terseness: I can imagine a GUI that would make it simple and visually obvious how the different atoms of a regular expression fit together, but such a GUI would spend a lot of visual bandwidth communicating which combinations are legal and which are absurd. Expressing a regular expression as a string gives you absolutely no such feedback, but if you already know the regex you want to use, it's an awful lot faster to type it.

Lastly, the command line gets a good deal of power from meta-programming: most commands deal with a loosely structured stream of text, and a set of commands is a loosely structured stream of text. Specifically in POSIX environments, primitives like command-substitution ("$()" or backticks) and the xargs command are powerful ways to write commands that construct and execute other commands. If your diagram-based UI contains a set of primitives for launching commands and working with text, you're going to have to add a whole new set of primitives for working with diagrams.

[tikhonj]

As somebody who spent some time working with LabVIEW, I can safely say that drawing a circuit diagram is more difficult and less intuitive than using text. Now, maybe this is the fault of LabVIEW, but I think it's true in the general case as well.

[LukeShu]

I once had to use LabVIEW. In general, I agree with you, but I got the feeling that G (the language implemented in LabVIEW) might almost be a decent language if the only IDE for it (and the file format) didn't suck so badly.