24,410 research outputs found
Aspect−Oriented Programming with Type Classes
No full textWe consider the problem of adding aspects to a strongly typed language which supports type classes. We show that type classes as supported by the Glasgow Haskell Compiler can model an AOP style of programming via a simple syntax-directed transformation scheme where AOP programming idioms are mapped to type classes. The drawback of this approach is that we cannot easily advise functions in programs which carry type annotations. We sketch a more principled approach which is free of such problems by combining ideas from intentional type analysis with advanced overloading resolution strategies. Our results show that type-directed static weaving is closely related to type class resolution -- the process of typing and translating type class programs
Translating Generalized Algebraic Data Types to System F
No full textGeneralized algebraic data types (GADTs) extend ordinary
algebraic data types by refining the types of constructors with syntactic
equality constraints. This is highly useful and allows for novel applications
such as strongly-typed evaluators, typed LR parsing etc. To translate
GADTs we need to enrich the System F style typed intermediate
languages of modern language implementations to capture these equality
constraints. We show that GADTs can be translated to a minor extension
of System F where type equality proofs are compiled into System
F typable proof terms. At run-time proof terms evaluate to the identity.
Hence, they can be safely erased before execution of the program. We
provide evidence that our approach scales to deal with extensions where
equality is not anymore syntactic. The benefit of our method is that type
checking of target programs remains as simple as type checking in System
F. Thus, we can offer a light-weight approach to integrate GADTs
and extensions of it into existing implementations
Modular Generic Programming with Extensible Superclasses
No full text"Generics for the Masses" (GM) and "Scrap your Boilerplate" (SYB) are generic programming approaches based on some inenious applications of Haskell type classes. To achieve modularity, the GM and SYB approach have been extended by using some experimental language extensions such as abstraction over type classes and recursive instances. Hence, the type class encodings behind the GM and SYB approach become less practical and harder to understand.We show that none of these type class features are necessary if we use the single feature of extensible superclasses, the complement of subclass extension. We formalize type classes with extensible superclasses as the combination of a previously introduced type-passing translation scheme and a general type class framework. Our results shed some new light on the use of type classes to support generic programming
Jack Alive / Martin Dead : The Location of the "Author" in Jack London\u27s Martin Eden
No full textThis essay is an attempt to read Martin Eden, Jack Londonʼs autobiographical novel, in terms of the inextricable relationship between the author and the protagonist. Critics have often taken the unbalanced plot and the lack of ironic distance between narrator and character in Martin Eden as the technical weakness of London, but this paper argues that the achievement of this novel owes a great deal to the attachment of London to Martin. The unbalanced structure is a necessary product of the severe struggle of the author to kill his romantic alter ego. // Martin, who aspires to win Ruth Morse, tries to cross class boundaries by making a career of a writer. Even after realizing the emptiness of Ruth, who turns out to be nothing but a typical figure of the bourgeoisie, he somehow persists in loving her. The notion underlying here is that, for Martin, love, career and art are fundamentally inseparable. He objects to the aestheteʼs view of Brissenden on account of his separation of art from career. Martinʼs identity and life consist only in the triunity of love/career/art; the alternative is the repudiation of life. Thus, the unnatural delay of his disappointment in love can be regarded as Londonʼs strategy to set the suicide of Martin as the necessary consequence of the story. // By finishing the story and killing Martin, London finally detaches himself from Martin, reconstructs his self, and, unlike Martin, survives as a professional writer. In this sense, Martin Eden is a story about “writerʼs self-reconstruction.
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Letter from Martin Chizzick
No full textCongratulations to Duane Pearsall for receiving the Enterpreneur of the Year award; note on the letter was written by Pearsall and it mentions that Martin, the author of the letter, died in a airplane accident
Robert Martin Tiffin's Mystery Man Newspaper Articles
No full textAdvertiser-Tribune newspaper clippings featuring a story about Robert Martin (written by Nancy Kleinhenz), a local author from Tiffin (Ohio) who wrote under the pseudonym of Lee Roberts, and two of his short stories. Martin wrote mystery novels in his spare time, creating more than 22 mystery novels. For more information about Robert Martin and a list of books go to http://www.mysteryfile.com/RMartin/JBennett.html
Foundations for structured programming with GADTs
No full textGADTs are at the cutting edge of functional programming and become more widely used every day. Nevertheless, the semantic foundations underlying GADTs are not well understood. In this paper we solve this problem by showing that the standard theory of data types as carriers of initial algebras of functors can be extended from algebraic and nested data types to GADTs. We then use this observation to derive an initial algebra semantics for GADTs, thus ensuring that all of the accumulated knowledge about initial algebras can be brought to bear on them. Next, we use our initial algebra semantics for GADTs to derive expressive and principled tools — analogous to the well-known and widely-used ones for algebraic and nested data types — for reasoning about, programming with, and improving the performance of programs involving, GADTs; we christen such a collection of tools for a GADT an initial algebra package. Along the way, we give a constructive demonstration that every GADT can be reduced to one which uses only the equality GADT and existential quantification. Although other such reductions exist in the literature, ours is entirely local, is independent of any particular syntactic presentation of GADTs, and can be implemented in the host language, rather than existing solely as a metatheoretical artifact. The main technical ideas underlying our approach are (i) to modify the notion of a higher-order functor so that GADTs can be seen as carriers of initial algebras of higher-order functors, and (ii) to use left Kan extensions to trade arbitrary GADTs for simpler-but-equivalent ones for which initial algebra semantics can be derive
Experiences Using Large Scale Video Walls for Distance Education
No full textWe describe our experiences building and using the Rutgers Videowall, a low-cost telepresence system that has been used teaching 15 courses and colloquia. By relaxing typical spatial telepresence features, such as background continuity, we greatly reduced costs and gained flexibility in the rooms it could be deployed in. The lower costs and room flexibility enabled academic departments to use the wall, in contrast to traditional telepresence systems which remained inaccessible. We found that the Videowall’s spatial distortions did not have a significant impact on useability, as our initial survey results show that students had an overall positive experience.Technical report DCS-tr-72
Hans Martin Schwarz Collection 1934 - 1938
No full textThis collection contains clippings of articles by Hans Martin Schwarz (1917, Hamburg – 2006, New York, better known as Martin Ebon), published between 1934 and 1938 in German-Jewish newspapers on a wide variety of subjects such as sports, emigration, the political situation in Germany, and religious attitudes of the young. It also contains reviews of his books "Einer wie Du und Ich" and "Heiteres, Besinnliches, Nachdenkliches."digitizedHans Martin Schwarz (1917, Hamburg – 2006, New York, better known as Martin Ebon), was a journalist and author. In Germany during the 1930s, he published in a variety of German-Jewish periodicals, primarily the Israelitisches Familienblatt. After immigrating to the United States in 1938, he changed his name to Martin Ebon, and published dozens of books in the areas of world affairs and parapsychology.Processe
Interview with Father James Martin
No full textIn May 2011, the Ignatian Faculty Scholars at Regis University conducted a Skype interview with Father James Martin, S. J., author of The Jesuit Guide to Almost Everything. The Scholars had used Father Martin’s book as a text for their year of study, which focused on Ignatian Spirituality, the Ignatian Pedagogical Paradigm, and teaching and learning at a Jesuit university. The interview was transcribed and is printed below. Father Martin reflects on the book, and responds to questions about the book itself, about finding God in all learners, and about the Church
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