apfelmus - Monoids and Finger Trees
In this article, we explain how monoids enable one and the same data structure, the finger tree, to implement virtually any other data structure; they arise by different choices of monoids. The technique is discussed using the examples of a list with random access and a priority queue. This post grew out of the big monoid discussion on the haskell-cafe mailing list. Introduction A very powerful ap
A Neighborhood of Infinity: Haskell Monoids and their Uses
Haskell is a great language for constructing code modularly from small but orthogonal building blocks. One of these small blocks is the monoid. Although monoids come from mathematics (algebra in particular) they are found everywhere in computing. You probably use one or two monoids implicitly with every line of code you write, whatever the language, but you might not know it yet. By making them ex
3分ã§è§£ã‚‹Haskellã®Arrowã®åŸºæœ¬ãƒ¡ãƒ¢ - よãã‚ã‹ã‚Šã¾ã›ã‚“
日本語ã§Arrowã®èª¬æ˜ŽãŒã‚ã¾ã‚Šè¦‹ä»˜ã‹ã‚‰ãªã‹ã£ãŸã®ã§ã€Haskell/Understanding arrows - Wikibooks, open books for an open worldã‚’èªã‚“ã§ç†è§£ã—ãŸã¤ã‚‚ã‚Šã®ãƒ¡ãƒ¢ã€‚オリジナルã®å›³ã‚’見ãªãŒã‚‰ã ã¨åˆ†ã‹ã‚Šã‚„ã™ã„ã‹ã‚‚。誤り・間é•ã„ãªã©ã€ä¹žã†ã”指摘。 b->cãªé–¢æ•°ã‚’Arrowãªã‚‹ã‹ã‚‰ãã‚Šç®±ã«å…¥ã‚Œã‚‹ã¨ã€ (Arrow a) => a b c ã“ã‚“ãªåž‹ã«ãªã‚‹ã€‚型パラメタãŒã€å¼•æ•°ã®bã¨è¿”値ã®cã®ãµãŸã¤ã€‚ Monadã¯ã€å€¤ã‚’ã‹ã‚‰ãã‚Šç®±ã«å…¥ã‚ŒãŸã‚‚ã®ã€‚ã‹ã‚‰ãã‚Šç®±ã¯åŸºæœ¬çš„ã«(ヘンãª)値。 Arrowã¯ã€é–¢æ•°ã‚’ã‹ã‚‰ãã‚Šç®±ã«å…¥ã‚ŒãŸã‚‚ã®ã€‚ã‹ã‚‰ãã‚Šç®±ã¯åŸºæœ¬çš„ã«(ヘンãª)関数。 arr :: (b -> c) -> a b c Monadã§ã¯ã€å€¤ã‚’ã‹ã‚‰ãã‚Šç®±ã«å…¥ã‚Œã‚‹é–¢æ•°returnãŒã‚る。 Arrowã§ã¯ã€é–¢æ•°ã‚’ã‹ã‚‰ãã‚Šç®±ã«å…¥ã‚Œã‚‹é–¢æ•°arrãŒã‚る。 (>>>)
ランã‚ング
ランã‚ング
ランã‚ング
リリースã€éšœå®³æƒ…å ±ãªã©ã®ã‚µãƒ¼ãƒ“スã®ãŠçŸ¥ã‚‰ã›
最新ã®äººæ°—エントリーã®é…ä¿¡
j次ã®ãƒ–ックマーク
kå‰ã®ãƒ–ックマーク
lã‚ã¨ã§èªã‚€
eコメント一覧を開ã
oページを開ã
{{#tags}}- {{label}}
{{/tags}}