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Re: [Scheme-reports] command-line and invocation manner

On 09/18/2013 05:58 PM, Alex Shinn wrote:
> For SRFI-22 or other shebang scripts, for use 1) you want
> just the script name.  For use 2) just the script name will
> also do the right thing.  This is what chibi-scheme does.

Kawa supports basic #!-invocation, though it doesn't claim
to support SRFI-22.  Instead, the recommended method is
more flexible - see http://www.gnu.org/software/kawa/Scripts.html
Such a script does get the expected result for (cdr (command-line)),
but doesn't set a "nice (car (command-line)):

$ cat ~/tmp/foo.scm
exec /usr/bin/kawa --script2 "$0" "$@"
(format #t "c-l: ~w~%" (command-line))
$ ~/tmp/foo.scm a "c d"
c-l: ("java kawa.repl --connect 53985 --script2 
/home/bothner/tmp/foo.scm" "a"
       "c d")

The --script2 option causes the Kawa reader to skip the first two lines.

This could be fixed by (for example) having --script2 have the
side-effect of setting a variable checked by the command-line function.
Cleaner might be a new flag that combines the effect of --script2
and setting the program name.

>     Compiling to an application (with a static "main" method):
>     $ kawa --main -C ~/tmp/foo.scm
>     (compiling /home/bothner/tmp/foo.scm to foo)
>     $ java foo abc "def ghi"
>     c-l: ("java foo" "abc" "def ghi")
> I guess if the OS supports natively running compiled Java
> then this would just be runnable as:
> $ foo abc "def ghi"
> c-l: ("foo" "abc" "def ghi")
> as in other compiled implementations?

Java is normally compiled to (one or more) .jar files.
An application commonly comes with shell and/or batch
scripts which is a wrapper that invokes the java command
on the .jar file (perhaps with some extra setup).  (Compiling
to a native application is unusual.  Alas GCJ is not
very active any more.)

I think the thing for Kawa to do is to define a property
(set with a -D option when invoking the JVM), and for
the (command-line) procedure to check if this property is set.
Or some similar convention.
	--Per Bothner
per@x   http://per.bothner.com/

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