[PRL] Calling Functions Written in Java from Scheme?

[Felix S Klock II]

On May 1, 2007, at 2:05 PM, Christine Hang wrote:

> Is there a way to call functions written in Java from Scheme?

There are a number of Scheme implementations written in Java that  
provide reasonable FFI's to communicate with Java.  So, assuming that  
you haven't tethered yourself to the feature set a particular Scheme  
implementation, you could use one of them.  (Of course, if your main  
Scheme program is of significant size, then you are probably relying  
on features its implementation provides beyond RnRS.  But I digress.)

The JVM-based Scheme implementation I have the most experience with  
is Kawa.  Its not 100% R5RS-compliant (at least not by default), but  
it was reasonably fast and provided a suitable environment for  
exploring Java libraries interactively.
http://www.gnu.org/software/kawa/
In particular this section of its manual documents how to call Java  
methods from Scheme:
http://www.gnu.org/software/kawa/Method-operations.html

An alternative is JScheme, whose Javadot notation for its FFI is  
popular.
http://jscheme.sourceforge.net/jscheme/doc/javadot.html
I do not have personal experience using JScheme; I only know it  
because the Javadot notation was selected for use in Common Larceny.

(There are many other JVM-based Scheme systems; SISC, Bigloo, ...)

-Felix