why learn haskell

Don't say much nonsense, just open up.Please refer to other articles for environment construction. Here is an empty framework to illustrate how to render simple data on a page A: After defaultlayout , you can simply use where to bring the data structure you need, which can be used in the [| |] Use functions and data to render the values you need.[whamlet| |] Can be stacked arbitrarily, but only with one where. This conforms to Haskell's standard syntax.Because do is the standard syntax for

function becomes GRANDFATHER: sheep-> maybe sheepgrandfather M = (just m) 'comb' father If you require a grandfather, add a mother function similar to father. If you do this, you can skip the exception because the comb function has already been used for consideration. To write this step, we have introduced monad without knowing it. The comb function is actually a> = function, plus the return function and> function, and it is officially promoted to monad. The so-called monad is similar to

Haskell's native data structure is not efficient for large-scale mathematical operations. Using list to store vectors or matrices is inefficient. Fortunately, Haskell has a wealth of third-party libraries that can be used to complete this operation with a powerful professional mathematical library. We will introduce the hmatrix library today. 1. Installation Development Environment: MacOSX 10.5 1. Install the dependent Library GSL (GNU Scientific L

Mozart-oz The mozart-oz language is a new generation of Computer languages jointly developed by Universit ät des Saarlandes, Swedish Institute of Computer Science, and Universit é catholique de Louvain.The language itself has the shadows of haskell, lisp, prolog, c, perl, java, and so on. It has almost all the features you want, such:Constrained programming features:In processing complex constraints, Languages provide search engines., We only need to

This article mainly introduces the multi-threaded server implemented by haskell. for details, refer to the following code: Module Main where Import Network. SocketImport Control. Concurrent Main: IO ()Main = doSock BindSocket sock (SockAddrInet 4242 iNADDR_ANY)Listen sock 10240.MainLoop sock MainLoop: Socket-> IO ()MainLoop sock = doConn ForkIO $ runConn connMainLoop sock RunConn: (Socket, SockAddr)-> IO ()RunConn (sock, tcp) = doSms lt;-recv

Data.bytestringString is a synonym for [Char], and there is a performance problem with the inertia of list on use.When working with large binary files, you can use ByteString instead of String.The ByteString contains the Lazy module Data.ByteString.Lazy and the Strict module data.bytestring.Where the Lazy module uses chunks (64K data blocks) internally.Prelude> import qualified Data.ByteString.Lazy as BPrelude B> import qualified Data.ByteString as SPrelude B S> B.pack [99,97,110]"can"Prelude B

Bitraversableclass (Bifunctor t, Bifoldable t) => Bitraversable t where bitraverse :: Applicative f => (a -> f c) -> (b -> f d) -> t a b -> f (t c d) bitraverse f g = bisequenceA . bimap f gbisequenceA :: (Bitraversable t, Applicative f) => t (f a) (f b) -> f (t a b)bisequenceA = bitraverse id idBitraversable is a type class. Used primarily to traverse two-tuple data structures.Either is a bitraversable.instance Bitraversable Either where bitraverse f _ (Left a) = Left (,) It's a bitraversabl

Parser typedata ParsecT s u m atype Parsec s u = ParsecT s u Identitytype Parser = Parsec String () Data parsect s U m AParsect with four types of parameters: Data flow type S, User state type U, underlying monad type M, return type A.Parsect is a monad converter. Type parsec s u = parsect s U IdentityThe parsec type is the Parsect type, and the underlying monad type is specific to Identity. Type Parser = Parsec String ()The Parser type is a special type of parsec, the data flow

Find-maximum-subarray Introduction to Algorithm Chinese third edition P42 page exercise 4.1-5Maximal sub-array algorithm for non-recursive linear time。。。 But Haskell didn't loop. , my writing is also described in the book .... However, this problem has a very good function of the advantages of writing this problem is too cool, elegant! completely into the pit The most gas is the problem on the Codewars, test all over but because a tab does not allo

conferences a day or two. When a reporter reporting the release of a product calls us, our product already has the same features. Among those who convert to functional programming, the common consideration has always been: learning this new, functional language "is good for you "; it's just like some people suggest that 30 minutes of gym activity every day will "make you healthy. However, this also implies the difficulty and effort required to do so. The LISP Language, unlike

Reply content:Basic syntax Coding techniques, coding specifications Various functions Various PHP modules Learn a CMS or two-time development Learn about Pdo,ado, data-driven layers, and learn MySQL on the go Error mechanism Object oriented Use a framework to help develop Magic method Design Patterns Reflection Write all kinds of tools, drivers. Write a small fra

computer language that is complex enough. And then just play. For example, Lisp is recommended to play scheme first. Prolog, Haskell, Ruby, io, Erlang,... You can have fun when you're free. Anyway, it's not going to take much time to learn any language at this time. If you just want to use, in fact, this time any language is not to learn, temporary learning, i

reading is not enough, actual combat is the most important, so-called learning, such as in the "Python core programming 2" after class exercises/learning some small script/etc., here are several sites for the Python script instance study: (1). Code share list--Python (2). Python Code Library (3). https:// searchcode.com/ (4). GitHub best choice, more search some related projects, look at someone else's code, copy the wheel!! 4. Advanced entryThe Python advanced section of learning can ref

C ++ experts learn advice and learn with an open mind ~~ [Reprinted], advice and learn modestly 1. Take C ++ as a new language learning (it has nothing to do with C! True .); 2. Read Thinking In C ++ instead of C ++. 3. read "The C ++ Programming Language" and "Inside The C ++ Object Model". Do not read them because they are difficult and we are beginners; 4. Do

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0 reply content: basic syntax Coding skills and coding specifications Various functions Various PHP modules Learning a cms or secondary development Learn about PDO, ADO, data driver layer, and mysql Error Reporting Mechanism Object-oriented Use a framework to help developers Magic Design Mode Reflection Write tools and drivers. Write a small framework by yourself (to be honest, you don't have so much energy to write it. You need to understand a lot of

PHP Learning Notes (a) easy to learn php,php learn notes Target planning: With the first lesson, we can learn about the PHP environment. 1. Understanding of the environment: 2. Access method: 3. Modify the code and view it. 4. Use of variables 5. Code indentation to have a hierarchical relationship, and the best between the code to keep blank lines 6. Variable N