Abstract
Functional programs are particularly well suited to formal manipulation by equational reasoning. In particular, it is straightforward to use calculational methods for program transformation. Well-known transformation techniques, like tupling or the introduction of accumulating parameters, can be implemented using calculation through the use of the fusion (or promotion) strategy. In this paper we revisit this transformation method, but, unlike most of the previous work on this subject, we adhere to a pure point-free calculus that emphasizes the advantages of equational reasoning. We focus on the accumulation strategy initially proposed by Bird, where the transformed programs are seen as higher-order folds calculated systematically from a specification. The machinery of the calculus is expanded with higher-order point-free operators that simplify the calculations. A substantial number of examples (both classic and new) are fully developed, and we introduce several shortcut optimization rules that capture typical transformation patterns.

Abstract
Records are a composite data type available in most programming and specification languages, but they are not natively supported by Alloy. As a consequence, users often find themselves having to simulate records in ad hoc ways, a strategy that is error prone and often encumbers the analysis procedures. This paper proposes a conservative extension to the Alloy language to support record signatures. Uniqueness and completeness is imposed on the atoms of such signatures, while still supporting Alloy's flexible signature hierarchy. The Analyzer has been extended to internally expand such record signatures as partial knowledge for the solving procedure. Evaluation shows that the proposed approach is more efficient than commonly used idioms.

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