Unfold/Fold Transformation (2007)
In this note we present the fundamentals of Burstall & Darlington's classical Transformation system for developing recursive programs, often called the unfold /fold framework. We will not...
Common-subexpression Elimination of Conditional Expressions (2007)
Oege De Moor, Jens Peter Secher
Consider a side-eect-free expression | possibly containing conditionals | represented as a directed acyclic graph. Such an expression can be linearised into a tree by introducing let-abstractions for...
From type inference to configuration (2002)
Morten Heine Sørensen, Jens Peter Secher
Abstract. A product line is a set of products and features with constraints on which subsets are available. Numerous configurators have been made available by product line vendors on the internet, in...
From Checking to Inference via Driving and Dag Grammars (2002)
Jens Peter Secher, Morten Heine Srensen
Abramov and Gluck have recently introduced a technique called URA for inverting rst order functional programs. Given some desired output value, URA computes a potentially in nite sequence of...
Abstract. Collapsed-jungle evaluation is an evaluation strategy for functional programs that can give super-linear speedups compared to conventional evaluation strategies such as call-by-need....
Abstract. Collapsed jungle evaluation is an evaluation strategy for functional programs that can give super-linear speedups compared to conventional evaluation strategies such as call-by-need....
Word Encoding Tree Connectivity Works (2000)
Stephen Alstrup, Jens Peter Secher, Mikkel Thorup
|Experimentally, we demonstrate the practical relevance of the theoretical trick of encoding trees in words. 1 Introduction In 1983, Gabow and Tarjan [3] showed that union- nd can be supported in...
Perfect Supercompilation (1999)
Perfect Supercompilation, Jens Peter Secher
Program Transformers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 7.2 The Metric Space of Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 7.3 Termination of...
Optimal on-line decremental connectivity in trees (1997)
Stephen Alstrup, Jens Peter Secher, Maz Spork
Let T be a tree with n nodes from which edges are deleted interspersed with m on-line connectivity queries. Even and Shiloach gave an O(n log n + m) algorithm to process edge deletion and m queries...
Optimal On-line Decremental Connectivity in Trees (1997)
Stephen Alstrup, Jens Peter Secher, Maz Spork
Let T be a tree with n nodes from which edges are deleted interspersed with m on-line connectivity queries. Even and Shiloach gave an O(n log n + m) algorithm to process edge deletion and m queries...
On perfect supercompilation (1996)
Jens Peter Secher, Morten Heine Sørensen
We extend positive supercompilation to handle negative as well as positive information. This is done by instrumenting the underlying unfold rules with a small rewrite system that handles constraints...