How can I run a Scheme expression from the command-line using neither a script saved in a file, nor starting the interactive shell?
The equivalent in Python would be: python -c "print 1+1". scheme (+ 1 1) just starts the interactive shell and shows the result inside it.
I installed guile and was able to have it execute code four ways:
$ guile <<< "(+ 1 1)"
GNU Guile 2.0.9
Copyright (C) 1995-2013 Free Software Foundation, Inc.
Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
This program is free software, and you are welcome to redistribute it
under certain conditions; type `,show c' for details.
Enter `,help' for help.
$1 = 2
$
$ echo "(+ 1 1)" | guile
GNU Guile 2.0.9
Copyright (C) 1995-2013 Free Software Foundation, Inc.
Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
This program is free software, and you are welcome to redistribute it
under certain conditions; type `,show c' for details.
Enter `,help' for help.
$1 = 2
scheme@(guile-user)>
$
$ echo "(+ 1 1)" > guile.script
$ guile < guile.script
GNU Guile 2.0.9
Copyright (C) 1995-2013 Free Software Foundation, Inc.
Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
This program is free software, and you are welcome to redistribute it
under certain conditions; type `,show c' for details.
Enter `,help' for help.
$1 = 2
$
Thanks to GAD3R for this one:
$ guile -c "(display (+ 1 1)) (newline)"
2
$
In all cases, I'm returned to my original shell prompt (indicated by the bare $ lines).
