[B! haskell] tetrylã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯

tetryl id:tetryl

haskellã«é–¢ã™ã‚‹tetrylã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯ (23)

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Haskellã¨éšä¼´ - Qiita
éšä¼´ éšä¼´ã¨ã„ã†ã®ã¯2ã¤ã®é–¢æ‰‹ã®é–¢ä¿‚ã®ã“ã¨ã§ã™. $ F : \mathcal{C} \to \mathcal{D} $, $ G : \mathcal{D} \to \mathcal{C} $ãŒã‚ã£ãŸã¨ã, éšä¼´$F \dashv G$ ã¨ã¯, è‡ªç„¶åŒåž‹ $\hom(F\cdot,\cdot) \cong \hom(\cdot,G\cdot)$ ã®ã“ã¨ã§ã™(ãŸã ã—ã“ã®åŒåž‹ã¯homã®å·¦å³ã‚’åŒæ™‚ã«å›ºå®šã—ã¦, 2å¤‰æ•°å¼•æ•°ã¨ã—ã¦ã¿ã¦è€ƒãˆã¾ã™). æ–‡ç« ã§èªã‚€ã‚ˆã‚Šå›³å¼ã‚’è¦‹ãŸã»ã†ãŒæ—©ã„ã§ã™. ã‚³ãƒ¼ãƒ‰ã«ã™ã‚‹ã®ã‚‚ç°¡å˜ã§ã™. éšä¼´ã¯åœè«–ã§ã¯é‡è¦ãªæ¦‚å¿µã§ã™. ãã“ã§Haskellã§ã®éšä¼´ã«ã¤ã„ã¦è¦‹ã¦ã„ãã¾ã™. ä¾‹ (æ®‹å¿µãªã“ã¨ã«)Haskellã§ã®éšä¼´ã®ä¾‹ã¯ãã“ã¾ã§å¤šããªã„ã§ã™. ã¨ã„ã†ã®ã‚‚, Haskellã§ã‚ˆãè¦‹ã‚‹é–¢æ‰‹(Maybe, List, Either aãªã©)ã«ã¯éšä¼´ãŒå˜åœ¨ã—ãªã„ã“ã¨ãŒç°¡å˜ã«ç¤ºã›ã‚‹
tetryl 2017/02/08
haskell

åœè«–
ãƒªãƒ³ã‚¯
Haskellã§å¦ã¶åœè«–ãƒ»å…¥é–€ç·¨ã€€å†™åƒã‚’å¯¾è±¡ã« - bitterharvestâ€™s diary
ï¼‘ï¼Žåœã®å®šç¾© ä¸€èˆ¬çš„ã«ã€åœã¯æ¬¡ã®ã‚ˆã†ã«å®šç¾©ã•ã‚Œã¦ã„ã‚‹ã€‚åœã¯ï¼•ã¤ã®è¦ç´ ã¨äºŒã¤ã®æ¡ä»¶ã«ã‚ˆã‚Šæ§‹æˆã•ã‚Œã‚‹ã€‚ï¼•ã¤ã®è¦ç´ ã¯æ¬¡ã®ã‚ˆã†ã«ãªã£ã¦ã„ã‚‹ã€‚ (1) å¯¾è±¡ åœã¯å¯¾è±¡ã‚’æœ‰ã™ã‚‹ã€‚å¯¾è±¡ã¯ã€é€šå¸¸ã¯å¤§æ–‡å—ã‚’ç”¨ã„ã¦ã€$A,B,C,..$ã¨è¡¨ã™ï¼ˆå¯¾è±¡ã¯å¤šãã®å ´åˆä½•ã‹ã®é›†ã¾ã‚Šã§ã‚ã‚‹ã€‚ä¾‹ãˆã°ã€é›†åˆãªã©ãŒå¯¾è±¡ã«ãªã‚‹ã€‚ã—ã‹ã—ã€é›†åˆã®è¦ç´ ã¯ã“ã®å ´åˆå¯¾è±¡ã¨ã¯ã„ã‚ãªã„ï¼‰ã€‚ (2) å°„ åœã¯å¯¾è±¡ï¼ˆè¤‡æ•°ã®å ´åˆã‚‚å¯ï¼‰ã‹ã‚‰å¯¾è±¡ï¼ˆã“ã¡ã‚‰ã‚‚è¤‡æ•°ã®å ´åˆå¯ï¼‰ã¸ç§»ã™å°„ã‚’æœ‰ã™ã‚‹ã€‚å°„ã¯ã€é€šå¸¸å°æ–‡å—ã‚’ç”¨ã„ã¦ã€$f,g,h,..$ã¨è¡¨ã™ï¼ˆã“ã‚Œã¾ã§ç¿’ã£ã¦ããŸé–¢æ•°ã¯å°„ã¨ãªã‚‹ãŒã€å°„ã¨ãªã‚‹ã®ã¯é–¢æ•°ã ã‘ã§ã¯ãªã„ã€‚ã“ã‚Œã‹ã‚‰èª¬æ˜Žã™ã‚‹ãƒ¢ãƒŽã‚¤ãƒ‰ã®å ´åˆã¯ã“ã‚Œã¾ã§ã®é–¢æ•°ã¨ã¯ç•°ãªã‚‹ï¼‰ã€‚ (3) ãƒ‰ãƒ¡ã‚¤ãƒ³ã¨ã‚³ãƒ‰ãƒ¡ã‚¤ãƒ³ å°„ã®å‡ºç™ºï¼ˆå…¥åŠ›ï¼‰å´ã®å¯¾è±¡ã‚’ãƒ‰ãƒ¡ã‚¤ãƒ³ã¨ã„ã„ã€åˆ°ç€ï¼ˆå‡ºåŠ›ï¼‰å´ã®å¯¾è±¡ã‚’ã‚³ãƒ‰ãƒ¡ã‚¤ãƒ³ã¨ã„ã†ã€‚ (4) æ’ç‰å°„ å°„ã¯æ’ç‰å°„$id$ã‚’æœ‰ã™ã‚‹ã€‚æ’ç‰å°„ã¯è‡ªåˆ†ã‹ã‚‰è‡ªåˆ†
tetryl 2016/07/29
åœè«–

haskell
ãƒªãƒ³ã‚¯
A Neighborhood of Infinity: You Could Have Invented Monads! (And Maybe You Already Have.)
You Could Have Invented Monads! (And Maybe You Already Have.) A more permanent version of this article is stored at GitHub. Please link to that rather than to here. If you hadn't guessed, this is about monads as they appear in pure functional programming languages like Haskell. They are closely related to the monads of category theory, but are not exactly the same because Haskell doesn't enforce t
tetryl 2016/05/08
haskell

monad
ãƒªãƒ³ã‚¯
What's the meaning of algebraic data type?
I'm reading a book about Haskell, a programming language, and I came across a construct defined "algebraic data type" that looks like data WeekDay = Mon | Tue | Wed | Thu | Fri | Sat | Sun That simply declares what are the possible values for the type WeekDay. My question is what is the meaning of algebraic data type (for a mathematician) and how that maps to the programming language construct?
tetryl 2015/11/10
haskell
ãƒªãƒ³ã‚¯
category-extras
category-extras: A meta-package documenting various packages inspired by category theory The obsolete category-extras package provided a monolithic set of modules designed for the use of category theory in Haskell. It was exploded into more focused, self-contained packages (listed in the dependencies below); this meta-package documents where the code has gone. In addition to the core definitions,
tetryl 2014/04/20
haskell
ãƒªãƒ³ã‚¯
Haskell Live: A Live Coding Adventure
Episode 2: Time To Refactor Wherein we review the code from our last episide, fix some bugs, alleviate some code smells, refactor some things to improve clarity and reduce redundancy, and introduce the concept of failed board parsing with error reporting. I've also posted a list of the tools I use to set up my environment. github Get the code! comment Discuss this episode on GitHub Issues! info We
tetryl 2014/03/18
haskell
ãƒªãƒ³ã‚¯
Reddit - Dive into anything
The Haskell programming language community. Daily news and info about all things Haskell related: practical stuff, theory, types, libraries, jobs, patches, releases, events and conferences and more...
tetryl 2013/11/05
Haskell
ãƒªãƒ³ã‚¯
ã€ŽThe Evolution of a Haskell Programmerã€
See Iavor Diatchkiâ€™s page â€œThe Evolution of a Programmerâ€ for the â€œoriginalâ€ (though he is not the author), and also below for the story behind this version. (This page has been translated into the Serbo-Croatian language by Anja Skrba from Webhostinggeeks.com. Thanks, Anja, for all your hard work!) Freshman Haskell programmer fac n = if n == 0 then 1 else n * fac (n-1) Sophomore Haskell programme
tetryl 2013/02/01
haskell
ãƒªãƒ³ã‚¯
Things that amuse me
Quicksort in Haskell Quicksort is a commonly used example of how succinct Haskell programming can be. It usually looks something likes this: qsort :: (Ord a Bool) => [a] -> [a] qsort [] = [] qsort (x:xs) = qsort (filter (<= x) xs) ++ [x] ++ qsort (filter (> x) xs) The probl em with this function is that it's not really Quicksort. Viewed through sufficently blurry glasses (or high abstraction altitu
tetryl 2013/01/28
haskell

FP
ãƒªãƒ³ã‚¯
Haskell - Wikibooks
Haskellã¯é–¢æ•°åž‹è¨€èªžã§ã‚ã‚Šã€ä»–ã®ãƒ—ãƒã‚°ãƒ©ãƒŸãƒ³ã‚°è¨€èªžã‚’è§¦ã£ãŸã“ã¨ã®ã‚ã‚‹èªè€…ãªã‚‰ã€Haskellã®ã‚„ã‚Šæ–¹ã¯ä»–ã®è¨€èªžã¨ã¯å¤šå°‘ç•°ãªã£ã¦ã„ã‚‹ã“ã¨ãŒåˆ†ã‹ã‚‹ã§ã—ã‚‡ã†ã€‚ Haskellã®ç‹¬è‡ªæ€§ã¯äºŒã¤ã‚ã‚Šã¾ã™ã€‚ä¸€ã¤ã¯ã€ã€Œç´”ç²‹ã€é–¢æ•°åž‹è¨€èªžã§ã‚ã‚‹ã“ã¨ã§ã™ã€‚ç´”ç²‹é–¢æ•°åž‹è¨€èªžã§ã¯ã€åŒã˜é–¢æ•°ã‚’åŒã˜å¼•æ•°ã§å‘¼ã³å‡ºã—ãŸå ´åˆã€å¿…ãšåŒã˜æˆ»ã‚Šå€¤ã«ãªã‚‹ã“ã¨ãŒä¿è¨¼ã•ã‚Œã¾ã™ã€‚äºŒã¤ç›®ã¯ã€HaskellãŒæ¥µã‚ã¦ç¾ä»£çš„ãªåž‹ç†è«–ã‚’å‚™ãˆã¦ã„ã‚‹ã“ã¨ã§ã™ã€‚Haskellã§ã¯ã€åž‹ã‚¯ãƒ©ã‚¹ã‚„ä»£æ•°çš„ãƒ‡ãƒ¼ã‚¿åž‹ãªã©ã®åž‹ã‚’æ‰±ã†ã“ã¨ãŒã§ãã¾ã™ã€‚ã“ã‚Œã‚‰ã®é›£è§£ãªæ¦‚å¿µã¯ã€ä»Šã¯å…¨ãç†è§£ã§ããªã„ã‹ã‚‚ã—ã‚Œã¾ã›ã‚“ãŒã€ã“ã®æœ¬ã‚’èªã¿çµ‚ãˆãŸå¾Œã«ã¯ã€ã‚ˆã‚Šèº«è¿‘ãªã‚‚ã®ã«æ„Ÿã˜ã‚‰ã‚Œã‚‹ã§ã—ã‚‡ã†ã€‚ ã•ã¦ã€HaskellerãŸã¡ã¯ã“ã®è¨€èªžã®ã©ã“ã«é…åŠ›ã‚’æ„Ÿã˜ã¦ã„ã‚‹ã®ã§ã—ã‚‡ã†ã‹ã€‚ãƒ¦ãƒ‹ãƒ¼ã‚¯ã§æ–°ã—ã„æ„Ÿè¦šã‚’å¾—ã‚‰ã‚Œã‚‹ã‹ã‚‰ã§ã—ã‚‡ã†ã‹ã€‚ã—ã‹ã—ã€Haskellã®æœ€ã‚‚å„ªã‚ŒãŸæ€§è³ªã¯ã€ç´”ç²‹é–¢æ•°ã®ã¿ã«ã‚ˆã£ã¦æ›¸ã‹ã‚Œã¦ã„ã‚‹ã“
tetryl 2012/04/26
haskell
ãƒªãƒ³ã‚¯
What's Wrong with the For Loop
Closures in Java are a hot topic of late. A few really smart people are drafting a proposal to add closures to a future version of the language. However, the proposed syntax and the linguistic addition are getting a lot of push back from many Java programmers. Today, Elliotte Rusty Harold posted his doubts about the merits of closures in Java. Specifically, he asks "Why Hate the for Loop?": I donâ€™
tetryl 2012/03/01
haskell
ãƒªãƒ³ã‚¯
Programming Language Egison
Egison - ãƒ—ãƒã‚°ãƒ©ãƒŸãƒ³ã‚°è¨€èªžâ†’ English Version Egisonã¨ã¯ï¼Ÿ Egisonã¯å¼·åŠ›ãªãƒ‘ã‚¿ãƒ¼ãƒ³ãƒžãƒƒãƒæ©Ÿèƒ½ã‚’ã‚‚ã¤é–¢æ•°åž‹è¨€èªžã§ã™ï¼Ž Egisonã‚’ä½¿ã†ã¨ï¼Œç´”ç²‹ã«å¸°ç´çš„ã«ã¯è¡¨ã›ãªã„ãƒ‡ãƒ¼ã‚¿ï¼Œä¾‹ãˆã°ï¼Œé›†åˆã‚„ï¼Œå¤šé‡é›†åˆï¼Œ ã¾ãŸç’°ã‚„ç¾¤ã¨ã„ã£ãŸä»£æ•°æ§‹é€ ãªã©ã®ãƒ‘ã‚¿ãƒ¼ãƒ³ãƒžãƒƒãƒã‚’ç›´æ„Ÿçš„ã«è¡¨ç¾ã™ã‚‹ã“ã¨ãŒã§ãã¾ã™ï¼Ž Egisonã®ãã®ä»–ã«ä»¥ä¸‹ã®ã‚ˆã†ãªç‰¹å¾´ãŒã‚ã‚Šã¾ã™ï¼Ž é…å»¶è©•ä¾¡ ã‚¤ãƒ³ã‚¹ãƒˆãƒ¼ãƒ«ã®æ–¹æ³• Egisonã¯Haskellã‚’ä½¿ã£ã¦å®Ÿè£…ã•ã‚Œã¦ã„ã¾ã™ï¼Ž Egisonã¯Hackageã®ãƒ‘ãƒƒã‚±ãƒ¼ã‚¸ã¨ã—ã¦é…å¸ƒã•ã‚Œã¦ã„ã¾ã™ï¼Ž Egisonã‚’ã‚¤ãƒ³ã‚¹ãƒˆãƒ¼ãƒ«ã™ã‚‹ã«ã¯ï¼ŒGHCã¨ Cabal-installãŒã‚¤ãƒ³ã‚¹ãƒˆãƒ¼ãƒ«ã•ã‚Œã¦ã„ã‚‹å¿…è¦ãŒã‚ã‚Šã¾ã™ï¼Ž Haskell Platformã‚’ã‚¤ãƒ³ã‚¹ãƒˆãƒ¼ãƒ«ã™ã‚Œã°ï¼Œ ãã®ä¸¡æ–¹ãŒè‡ªå‹•ã§ã‚¤ãƒ³ã‚¹ãƒˆãƒ¼ãƒ«ã•ã‚Œã¾ã™ï¼Ž Hasekll Platformã‚’ã‚¤ãƒ³ã‚¹ãƒˆãƒ¼ãƒ«ã—ãŸã‚‰ï¼Œã‚³ãƒž
tetryl 2012/02/22
haskell

PL
ãƒªãƒ³ã‚¯
Dropbox Tech Blog
Dropbox.Tech( Developers Application Front End Infrastructure Machine Learning Mobile Security Culture )
tetryl 2012/01/04
haskell
ãƒªãƒ³ã‚¯
Why is this simple haskell algorithm so slow?
tetryl 2011/12/29
haskell
ãƒªãƒ³ã‚¯
News
Take a look at five reasons businesses choose Scrive's e-signatures and digital identity services to help simplify and moderate their compliance Read articleLegitify, a leading remote online notarisation solution, has entered into a partnership with Scrive to offer electronic notarisation. Read articleFind out how eIDAS 2.0 is driving the transition to digital in Europe. Discover the benefits and
tetryl 2011/12/29
haskell

monad
ãƒªãƒ³ã‚¯
Partial Function Considered Harmful - ç´”ç²‹é–¢æ•°ç©ºé–“
ã“ã®è¨˜äº‹ã¯ã€Haskell Advent Calendar 2011 25æ—¥ç›®ã®è¨˜äº‹ã¨ã—ã¦æ›¸ã‹ã‚Œã¾ã—ãŸã€‚ æ¦‚è¦ Haskellã€ã‚ã‚‹ã„ã¯ãã®ä»–ã®ãƒ—ãƒã‚°ãƒ©ãƒŸãƒ³ã‚°è¨€èªžã§ã¯ ã€Œéƒ¨åˆ†é–¢æ•°(Partial Function)ã€ ã¨å‘¼ã°ã‚Œã‚‹ã‚‚ã®ãŒæ¨™æº–ãƒ©ã‚¤ãƒ–ãƒ©ãƒªã«å˜åœ¨ã—ãŸã‚Šã€ å®šç¾©ã—ãŸã‚Šã™ã‚‹ã“ã¨ãŒã§ãã¾ã™ã€‚ ä»Šå›žã¯ãã‚Œã‚‰ãŒæœ‰å®³ã§ã‚ã‚‹ã¨ã„ã†è€ƒãˆã¨ã€ ä»£æ›¿ã®ç´¹ä»‹ã‚’ã—ã‚ˆã†ã¨æ€ã„ã¾ã™ã€‚ éƒ¨åˆ†é–¢æ•°ã¨ã¯ éƒ¨åˆ†é–¢æ•°(Partial Function)ã¨ã¯ã€ é›†åˆã®è¨€è‘‰ã§è¨€ã†ã¨ã€ å®šç¾©åŸŸ(domain)ã®è¦ç´ ã«å¯¾ã—ã¦ã€å€¤åŸŸ(range)ã®å€¤ãŒé«˜ã€…1ã¤å¯¾å¿œä»˜ã‘ã‚‰ã‚Œã‚‹ ã‚ˆã†ãªå¯¾å¿œä»˜ã‘ã®ã“ã¨ã§ã™ã€‚ Haskellã§ã¯ ã€Œçµæžœã®å€¤ãŒå¼•æ•°ã«ã‚ˆã£ã¦ã¯å®šç¾©ã•ã‚Œãªã„ã“ã¨ãŒã‚ã‚Šå¾—ã‚‹ã€ é–¢æ•°ã ã¨è¨€ãˆã¾ã™ã€‚ ä¾‹ãˆã°ã€æ•´æ•°ã®å‰²ã‚Šç®—ã‚’è¡Œã†é–¢æ•° div :: (Int, Int) -> Int ã¯ã€ (1, 0) ã«å¯¾ã—ã¦ã¯å®šç¾©ã•ã‚Œã¾ã›ã‚“ã€‚ Ha
tetryl 2011/12/27
haskell
ãƒªãƒ³ã‚¯
House
Haskell User's Operating System and Environment Note: Kenny Graunke has made available a a newer version of House, ported to GHC 6.8.2 (October 2008) House is a demo of software written in Haskell, running in a standalone environment. It is a system than can serve as a platform for exploring various ideas relating to low-level and system-level programming in a high-level functional language. More
tetryl 2011/12/23
haskell

os
ãƒªãƒ³ã‚¯
Google Code Archive - Long-term storage for Google Code Project Hosting.
tetryl 2011/11/23
c++

haskell

oss
ãƒªãƒ³ã‚¯
Yesod Web Framework for Haskell
Yesod is a Haskell web framework for productive development of type-safe, RESTful, high performance web applications. Yesod is a Haskell web framework for productive development of type-safe, RESTful, high performance web applications. Why Yesod? Turn runtime bugs into compile-time errors Yesod believes in the philosophy of making the compiler your ally, not your enemy. We use the type system to e
tetryl 2011/10/17
haskell

WAF
ãƒªãƒ³ã‚¯
foldrãŒåŠ¹çŽ‡çš„ã«å‹•ä½œã™ã‚‹æ¡ä»¶ - www.kotha.netã®è£
eagerãªè¨€èªžã§ã¯foldrã¯ãƒªã‚¹ãƒˆã®é•·ã•ã«æ¯”ä¾‹ã™ã‚‹ã‚¹ã‚¿ãƒƒã‚¯ã‚’æ¶ˆè²»ã™ã‚‹ã€‚GHCã§ã‚‚(+)ã®ã‚ˆã†ãªæ£æ ¼ãªé–¢æ•°ã§ç•³ã¿è¾¼ã‚‚ã†ã¨ã™ã‚Œã°åŒæ§˜ã«O(n)ã®æŒ¯ã‚‹èˆžã„ã«ãªã‚‹ã€‚ {-# OPTIONS_GHC -O0 #-} import Data.List(foldl') main = do n <- readLn print $ foldr (+) 0 [1..n] -- O(n)ã‚¹ã‚¿ãƒƒã‚¯ã€O(1)ãƒ’ãƒ¼ãƒ— print $ foldl (+) 0 [1..n] -- O(n)ã‚¹ã‚¿ãƒƒã‚¯ã€O(n)ãƒ’ãƒ¼ãƒ— print $ foldl' (+) 0 [1..n] -- O(1)ã‚¹ã‚¿ãƒƒã‚¯ã€O(1)ãƒ’ãƒ¼ãƒ— ä¸€æ–¹ã€foldrã‚’ä½¿ã£ã¦åŠ¹çŽ‡çš„ã«å®Ÿè£…ã§ãã‚‹é–¢æ•°ã‚‚Haskellã«ã¯å˜åœ¨ã™ã‚‹ã€‚ä¾‹ãˆã°ä»¥ä¸‹ã¯concatã®ç«‹æ´¾ãªå®šç¾©ã§ã‚ã‚Šã€O(1)ç©ºé–“ã§å‹•ä½œã™ã‚‹*1ã€‚ concat :: [[a]] -> [a] concat =
tetryl 2011/06/06
haskell

FP
ãƒªãƒ³ã‚¯
1 2 æ¬¡ã®ãƒšãƒ¼ã‚¸