Keywords and optimization

[robison at uiucdcsb.cs.uiuc.edu]

For a language which incorporates optimization information very cleanly,
look at the FX language[1][2].  It introduces the notion of an "effect system"
which describes side effects in a manner analogous to the way a type system
describes types.  The effect system allows very aggressive but safe
optimization, documentation of side effects, and polymorphism.
FX programs can be strongly type checked and effect checked, that is
the effects are not just advice but checkable assertions.

Disclaimer: I've only read the reference manual and haven't used FX yet.
            But its the first LISP-like language I've seen which should 
	    run on stock hardware as fast as C.  

References

[1] John M. Lucassen and David K. Gifford, "Polymorphic Effect Systems",
    Proceedings of the Fifteenth Annual ACM SIGACT-SIGPLAN Symposium
    on Principles of Programming Languages (January 1988).

[2] FX-87 Reference Manual, David K. Gifford et al., MIT LCS TR-409,
    MIT Laboratory for Computer Science, September 1987.

Arch D. Robison
University of Illinois at Urbana-Champaign
	
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