| | |
Summary: Normalization by evaluation
for typed lambda calculus with coproducts
T. Altenkirch
P. Dybjer
¡
M. Hofmann
¢
P. Scott
£
April 10, 2001
Abstract
We solve the decision problem for simply typed lambda
calculus with strong binary sums, equivalently the word
problem for free cartesian closed categories with binary
coproducts. Our method is based on the semantical tech-
nique known as "normalization by evaluation" and in-
volves inverting the interpretation of the syntax into a
suitable sheaf model and from this extracting appropri-
ate unique normal forms. There is no rewriting theory in-
|
