Unix shell design [was Re: Yes, Unix can do batch renames - Re: Unix handles file extensions "very poorly"?]

Let's start with the "rm *" example. "rm *" is a particular invokation of rm that isn't commonly used -- it's an exceptional case that someone really wants to delete all files in a particular directory. Is it annoying to anyone to either answer "y" to an "Are you sure?" prompt or type in "rm -y *" to autoconfirm in these few cases?

Even if it is slightly more work, think of the tradeoff that's being made: you're saving every Unix user the pain of accidentally screwing themselves via a typo -- and just as evidenced by responses on this list, *everyone* (well, mostly everyone) has managed to do this at least once or knows someone who has.

Another example, from Symbolics Genera (which I've been spending a fair amount of time with). The Command line in the Lisp Listener has a few wonderful features which manage to be both powerful *and* helpful at the same time. (It also has a few warts, but I believe the ideas present in it are something worthy of being brought back). First of all, commands are verbose and self-descriptive -- for example, the command to copy a file is: :Copy File That's a lot of typing (especially for more lengthy commands like "Show Machine Configuration". Fortunately this has been dealt with by only requiring the user to type as much of a command needed to disambiguate it -- "S Mac" works for the latter case, "Cop F" is enough for the former.

Once you've finished typing "Copy File" the listener immediately appends some simple context-sensitive information hinting at the arguments, so you end up the below on your screen: :Copy File (pathnames of files) _ What if you've forgotten the name of the file you want to copy? Hit Ctrl-/ and it'll give you a list of files in the most recently accessed directory, or will show files that start with a path you've partially completed. You can then either type one in from the list and hit the "Complete" key or click on one of the filenames listed. (The commandline is mouse-sensitive as well.) At this point the command prompt helps you again with the second argument (hinting that you need to type in the "to" portion of the copy), and you have: :Copy file (pathnames of files) FOO:>bar>baz.lisp;4 (to [default <most recently used path>]) _ And you type in the destination, and again are prompted: :Copy file (pathnames of files) FOO:>bar>baz.lisp;4 (to [default <most recently used path>]) FOO:>bar>quux.lisp (keywords) _ It's now hinting that "Copy File" takes optional keywords. If you don't need them, hit "Return" to execute the command, otherwise you can hit "Ctrl-/" (consistency!) to see a list of possible keyword arguments and a brief documentation string for each, as seen (excerpted) below: These are the possible keyword arguments: :Byte Size Byte size in which to do copy operation :Copy Properties Properties of the file to be duplicated :Create Directories What to do if a destination directory does not exist :If Exists What to do if asked to copy to an existing file