Kevin Reid's blog

Something I still miss from the ORCA development shell for the Apple IIgs (at least, I think that's where it was) is the option to interpret a command name which is directory as a command to change to that directory; essentially letting you omit “cd ”.

The following command is not idempotent:

cat * > cat.txt

I was working on some automated document generation, building the process, revising the input document, and checking the results, and got tired enough of typing "make output/foo.txt && open output/foo.txt" and then going back and editing that line when I wanted to check the PDF version etc. that I wrote a tool which I hope will have more general application as well. I called it “maken”:

#!/bin/sh
# Make files and view the results.
make "$@" && open "$@"

Or it could be generalized into being a combinator, running any two commands, rather than just make and open, specified as the first two arguments:

#!/bin/sh
ca="$1"
shift
cb="$1"
shift
"$ca" "$@" && "$cb" "$@"

(Which, for the Haskell folks, should be called &&&, except that that would be annoying to enter in the shell.)