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Re: Several comments
> Marc> and "scheme-script" would always invoke "script-main" after loading a
> Marc> script.
> I can imagine going with that. Opinions, anyone else?
Can you explain your position on the other alternatives. In
particular the second one which is my preference:
"exec" "scheme-script" "$0" "$@"
(define (main arg1 arg2)
(write (+ (string->number arg1) (string->number arg2))))
(apply main (script-arguments))
I forgot to mention that it allows scripts to be compiled to an
executable program (i.e. a.out), as well as to a "fasl" file. For
this to work, "script-arguments" behaves as follows depending on the
1) In the dynamic extent of a "load": (script-arguments) signals the
error "Attempt to load a script in an inappropriate context". This
happens whether the file loaded is a source code file or a "fasl"
2) In all other contexts, and in particular during loading as a script
by scheme-script and during the execution of a compiled program:
(script-arguments) returns the command line arguments as a list of
For example, the above script could be compiled with Gambit to an
"a.out" simply with:
% gsc S.scm
% gcc S.c S_.c -lgambc
% a.out 100 200
There is no need for the compiler to know that it is compiling a
My third alternative, based on the implicit call of a "script-main"
procedure, requires the compiler to know it is compiling a script so
it has to be given a special compilation option, or detect that the
file being compiled starts with "#!" (actually it is a bit more
complicated because it is the linker that has to know it is generating
an executable and one of the source files was a script).