问题
When I tried the instructions at https://arclanguage.github.io/, after I entered "racket -f as.scm" I got "-bash: racket: command not found".
I also tried these instructions for downloading Arc on Linux: https://sites.google.com/site/arclanguagewiki/getting-started/install-arc I installed racket from download.racket-lang.org, and when I got to "./arc" in the Arc/Nu section, the output from the terminal was "env: racket: No such file or directory".
The Arc Language Wiki (linked to above) indicates that the official installation instructions are out of date, and says little about how to install Arc on OS X. I tried googling for a general solution to "command not found" and "No such file or directory" problems but couldn't find anything that let me fix the problem. I also tried moving my racket and arc downloads to different combinations of places.
回答1:
Arc runs on top of Racket, which although you've downloaded it, does not appear to be in PATH, the environment variable containing the list of folders that Bash searches for executables.
The immediate fix is to, instead of running Arc as racket -f as.scm, run it as /path/to/racket/bin/racket -f as.scm. (The Racket documentation points out that the Racket executable is in the bin folder of the Racket folder you downloaded).
Assuming that works, the fix is to add the Racket bin folder to your PATH variable. Open up ~/.bashrc in your favorite text editor, and add a line export PATH=/path/to/racket/bin:"$PATH".
Once you do this, you'll have to open a new Terminal before this change will take effect. But once you do, you should be able to just run racket -f as.scm, and it will work.
来源：https://stackoverflow.com/questions/29488718/installing-arc-on-os-x