Re: JACAL, scm

[Rob Browning]

Aubrey Jaffer <address@hidden> writes:

> Binding global properties to alter function behavior (essentially
> argument passing) is asking for trouble in a multi-threaded environment.
> For READ it isn't even necessary; if these properties were attached to
> the port, then multi-thread safety would follow.  Parameters like
> stack-depth, which are truly global, are best set from the command line.

No argument here.  I believe people have been talking about trying to
fix at least some of this soon, but they'll have to speak up as I
forget where that discussion ended.

>   guile -l ${SCHEME_LIBRARY_PATH}guile.init -l ${JACALDIR}guile.scm
>
> Why can Guile load multiple files from the command line, but not execute
> more than one expression?  Why can't Guile execute a command-line
> expression before entering interactive session?

Excellent questions.  I asked myself the same thing after banging my
head against the wall a few times on that front, and accordingly I've
rewritten much of guile's command line processing (in Scheme rather
than C) to fix these problems, but that code hasn't been committed
yet, and it definitely won't make it into 1.6.

That was deemed too big a change too close to the release, but expect
to see command-line improvements in 1.8.

> SCM's command line is capable of nearly anything which /bin/sh's is.  I
> script extensively with it and recommend it for Schemes aspiring to
> scripting languages.
>
> http://swissnet.ai.mit.edu/ftpdir/users/jaffer/slib.zip and
> http://swissnet.ai.mit.edu/ftpdir/users/jaffer/jacal.zip are my new
> versions.

OK, thanks.  Before I commit my code, I'll look at what SCM does and
compare it to the changes I made.  No reason the two should be
gratuitously incompatible, all other things being equal.

-- 
Rob Browning
rlb @defaultvalue.org, @linuxdevel.com, and @debian.org
Previously @cs.utexas.edu
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