Debugging - HaskellWiki 1 Stack trace 1.1 General usage Recent versions of GHC allow a dump of a stack trace (of all cost centres) when an exception is raised. A more detailed list of options can be found in the RTS section of the GHC user's guide. 1.2 Example -- test.hs crash = sum [1,2,3,undefined,5,6,7,8] main = print crash > ghc-7.6.3 test.hs -prof -auto-all -caf-all && . 2 Printf and friends The simplest approach is to use Debug.Trace.trace: trace :: String -> a -> a "When called, trace outputs the string in its first argument, before returning the second argument as its result.'" A common idiom to trace a function is: myfun a b | trace ("myfun " ++ show a ++ " " ++ show b) False = undefined myfun a b = ... The advantage is that disabling and enabling the trace takes only one line comment. You must keep in mind that due to lazy evaluation your traces will only print if the value they wrap is ever demanded. The trace function is located in the base package. A more powerful alternative for this approach is Hood. $ . $ .
DOAB: Directory of Open Access Books Abstract Increasingly, technology is at stake in toys, games and playing. With the immense popularity of computer games, questions concerning the role and function of technology in play have become more pressing. Technologie speelt een steeds belangrijkere rol in speelgoed en spellen. Design and Analysis of Algorithms Information Overview This core course covers good principles of algorithm design, elementary analysis of algorithms, and fundamental data structures. The emphasis is on choosing appropriate data structures and designing correct and efficient algorithms to operate on these data structures. Learning outcomes This is a first course in data structures and algorithm design. learn good principles of algorithm design; learn how to analyse algorithms and estimate their worst-case and average-case behaviour (in easy cases); become familiar with fundamental data structures and with the manner in which these data structures can best be implemented; become accustomed to the description of algorithms in both functional and procedural styles; learn how to apply their theoretical knowledge in practice (via the practical component of the course). Synopsis Program costs: time and space. Syllabus Reading list T.
Haskell comme un vrai! tlpl: Un tutoriel très court mais très dense pour apprendre Haskell. Merci à Oleg Taykalo vous pouvez trouver une traduction Russe ici: Partie 1 & Partie 2 ; Table of Content Je pense vraiment que tous les développeurs devraient apprendre Haskell. La plupart des langages partagent les mêmes fondamentaux : les variablesles bouclesles pointeursles structures de données, les objets et les classes Haskell est très différent. Plier son esprit à Haskell peut être difficile. Cet article sera certainement difficile à suivre. La manière conventionnelle d’apprendre Haskell est de lire deux livres. Cet article fait un résumé très dense et rapide des aspect majeurs d’Haskell. Pour les francophones ; je suis désolé. Cet article contient cinq parties : Note: Chaque fois que vous voyez un séparateur avec un nom de fichier se terminant par lhs, vous pouvez cliquer sur le nom de fichier et télécharger le fichier. 01_basic/10_Introduction/00_hello_world.lhs Introduction Install Tools: Don’t be afraid Functional
Introduction | Hackage The SchoolTool Book — The SchoolTool Book Concurrency Information Overview Computer networks, multiprocessors and parallel algorithms, though radically different, all provide examples of processes acting in parallel to achieve some goal. Learning outcomes At the end of the course the student should: understand some of the issues and difficulties involved in Concurrency be able to specify and model concuurent systems using CSP be able to reason about CSP models of systems using both algebraic laws and semantic models be able to analyse CSP models of systems using the model checker FDR Synopsis Processes and observations of processes; point synchronisation, events, alphabets. Syllabus Deterministic processes: traces, operational semantics; prefixing, choice, concurrency and communication. Reading list Course Text: A. Alternatives: A.W. Overheads: This year's slides will appear on the Course Materials page over the course of the term. Related research at the Department of Computer Science
Everything Your Professor Failed to Tell You About Functional Programming I've been trying to learn Haskell lately, and the hardest thing seems to be learning about monads. "Monads in Ruby" and "Monads for Functional Programming" helped me finally to break the ice, but more importantly, they gave me a glimpse behind the veil. I finally began to understand something that is trivial to people such as Philip Wadler, but something that never had been explained to me so succinctly. Monads as a Design Pattern Somewhere, somebody is going to hate me for saying this, but if I were to try to explain monads to a Java programmer unfamiliar with functional programming, I would say: "Monad is a design pattern that is useful in purely functional languages such as Haskell. Philip Wadler says, "Monads provide a convenient framework for simulating effects found in other languages, such as global state, exception handling, output, or non-determinism." The Java programmer could argue fairly, "Hey, Java has all those things, and monads aren't even mentioned in Design Patterns.
Hoogle Hoogle is a Haskell API search engine, which allows you to search many standard Haskell libraries by either function name, or by approximate type signature. Example searches: map (a -> b) -> [a] -> [b] Ord a => [a] -> [a] Data.Map.insert Enter your own search at the top of the page. The Hoogle manual contains more details, including further details on search queries, how to install Hoogle as a command line application and how to integrate Hoogle with Firefox/Emacs/Vim etc. I am very interested in any feedback you may have. Please email me, or add an entry to my bug tracker. doors :: Forgotten Books The Journal of Horticulture, Cottage Gardener, and Countr…A Journal of Horticulture, Rural and Domestic Economy, Botany and Natural Hi… by George W. JohnsonVol. 3 We know of one who would not have on the parlour chimney-shelf a dial with a seconds hand, because it made him see and feel how life lessens, as it were, drop by drop. What he would h… Door KnockersThe Famous Wm, Hall & Co, Line, Collected Since 1843; Now Made By Art Bras… by Art Brass Company Door Knockers: The Famous Wm, Hall& Co, Line, Collected Since 1843; Now Made By Art Brass Company, Inc was written by Art Brass Company in 1917. The Garden, 1907An Illustrated Weekly Journal of Gardening in All Its Branches by Unknown Author The Garden: An Illustrated Weekly Journal of Gardening in All Its Branches was written by in 1907. Keith's Magazine on Home Building, 1919 No. The Door of DreadA Secret Service Romance by Arthur Stringer Sadie Wimpel. Journal of the Congress of the Confederate States of Americ… May 2, 1864. by Alfred Austin