jscheme-user

[Jscheme-user] Accessing command line arguments?

[Kyle R. B. <kyl...@gm...>]

I see that the arguments to main in jscheme.REPL are handled in various way=
s
- as files to be loaded, as scheme expressions, or with support for a -main
proc-name arg1 ..., but is there a way of passing through command line
arguments so that they can be accessed by the scheme code being executed?

I'd like to use JScheme to create some command line utilities.  To do so I
need access to command line arguments, and stdin, stdout and stderr (the
last three appear to be available as System.in, System.out and System.err,
unless there is some JScheme replacement for them that I'm not aware of...)=
.

Thanks,

Kyle

--
---------------------------------------------------------------------------=
---
Wisdom and Compassion are inseparable.
        -- Christmas Humphreys
kyl...@gm...
http://www.neverlight.com/~mortis
---------------------------------------------------------------------------=
---

Re: [Jscheme-user] Accessing command line arguments?

[Timothy J H. <tjh...@br...>]

On Jan 23, 2006, at 10:04 PM, Kyle R. Burton wrote:

> I see that the arguments to main in jscheme.REPL are handled in =20
> various ways - as files to be loaded, as scheme expressions, or with =20=

> support for a -main proc-name arg1 ..., but is there a way of passing =20=

> through command line arguments so that they can be accessed by the =20
> scheme code being executed?

You can use the -main commandline argument which expects the next =20
string to be a Scheme procedure P
and it then grabs the remaining strings and bundles them into an array =20=

of Strings, L.
It then calls the Scheme procedure P on L.

For example, suppose that testing.scm is the following program

(define (testing L)
   (display (.getClass L))
   (newline)

   (display
     (map
       (lambda(x)
          (list x (.getClass x)))
       (array->list L)))
   (newline)
)

Then we can invoke jscheme and pass command line args to the testing =20
procedure
as follows:

     % java -cp ~/lib/jscheme.jar jscheme.REPL test.scm -main testing 1 =20=

2 3
     class [Ljava.lang.String;
     ((1 class java.lang.String) (2 class java.lang.String) (3 class =20
java.lang.String))

Is this what you are looking for?

Best,
---Tim---



>
> I'd like to use JScheme to create some command line utilities.=A0 To =
do =20
> so I need access to command line arguments, and stdin, stdout and =20
> stderr (the last three appear to be available as System.in , =20
> System.out and System.err, unless there is some JScheme replacement =20=

> for them that I'm not aware of...).
>
> Thanks,
>
> Kyle
>
> -- =20
> =
-----------------------------------------------------------------------=20=

> -------
> Wisdom and Compassion are inseparable.
> =A0=A0=A0=A0=A0=A0=A0=A0-- Christmas Humphreys
> kyl...@gm...=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=
=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0http://=20
> www.neverlight.com/~mortis
> =
-----------------------------------------------------------------------=20=

> -------