@ARTICLE{AlpuenteHanusLucasVidal05,
author       = {Alpuente, M. and Hanus, M. and Lucas, S. and Vidal, G.},
title        = {Specialization of Functional Logic Programs Based on Needed Narrowing},
year         = {2005},
journal      = {Theory and Practice of Logic Programming},
number       = {3},
pages        = {273-303},
volume       = {5},
abstract = {
Many functional logic languages are based on narrowing,
a unification-based goal-solving mechanism
which subsumes the reduction mechanism of functional languages and
the resolution principle of logic languages. Needed narrowing is
an optimal evaluation strategy which constitutes the basis of modern 
(narrowing-based) lazy functional logic languages. In this work, we present 
the fundamentals of partial evaluation in such languages. We provide 
correctness results for partial evaluation based on needed 
narrowing and show that the nice properties of this strategy are 
essential for the specialization process. In particular, the 
structure of the original program is preserved by partial evaluation
and, thus, the same evaluation strategy can be applied for the 
execution of 
specialized programs. This is in contrast to other partial evaluation
schemes for lazy functional logic programs which may change the 
program structure in a negative way.
Recent proposals for the partial evaluation of declarative 
multi-paradigm programs use (some form of) needed narrowing to perform 
computations at partial evaluation time. Therefore, our results 
constitute the basis for the correctness of such partial evaluators.
}
}