How is pattern matching in Scala implemented at the bytecode level? Is it like a series of if (x instanceof Foo) constructs, or something else? What are its performance implications? For example, given the following code (from Scala By Example pages 46-48), how would the equivalent Java code for the eval method look like? abstract class Expr case class Number(n: Int) extends Expr case class Sum(e1
Using a number of newer language features in Scala it's possible to implement a composable component system and create components using the so called Cake Pattern, described by Martin Odersky in the paper Scalable Component Abstractions and also in a recent talk. Several of the Scala features used in the Cake Pattern have corresponding Haskell features. For example, Scala implicits correspond to H
I read an article that SSH Daemon Service. But I want to run on Centos6.4. So I setup from official centos image with almost same istruction. Then I connect to centos sshd server, but connection is closed immediately. Here is the message. ssh root@localhost -p 49164 The authenticity of host '[localhost]:49164 ([127.0.0.1]:49164)' can't be established. RSA key fingerprint is 88:71:89:e5:30:91:78:5c
In Scala 2.9 to add custom methods to a library class (enrich or "pimp" it) I had to write something like this: object StringPimper { implicit def pimpString(s: String) = new { def greet: String = "Hello " + s } } As Scala 2.10 was released, I've read that it introduces implicit class definition which, theoretically, was meant to simplify the above task by removing the need in an implicit method r
I have changes to a file, plus a new file, and would like to use git stash to put them away while I switch to another task. But git stash by itself stashes only the changes to the existing file; the new file remains in my working tree, cluttering up my future work. How do I stash this untracked file?
In Firefox, I use Firebug which allows me to view every http request my ajax calls are making. I've switched over my development to Chrome and am liking it so far. My only complaint, however, is that the developer tools don't seem to allow you to view each ajax request. I've had it happen once where the Resources panel showed multiple requests to the same resource, but it's only done it once and n
I was able to use cabal-dev to build some packages that cabal was having issues with. ( help with cabal install package shadowing errors ). How does one then install and use them? I tried copying the package database files into the ~/.ghc/x86_64-linux-7.0.4/package.conf.d folder, and running ghc-pkg recache --user, but no luck. (They do show up in ghc-pkg now though).
I feel markdown succeeds where other markup languages fail because the author didn't try to create a new language, but rather codify what people were doing already (specifically in emails). From Markdown's home page: While Markdown’s syntax has been influenced by several existing text-to-HTML filters, the single biggest source of inspiration for Markdown’s syntax is the format of plain text email.
I recently inherited some OpenCV code. I installed openCV on my mac, built in in XCode, and then compiled and successfully ran my first openCV "hello world"-ish program. Now I'm trying to run the code I was given, but I get errors that lead me to believe it's an issue with the original code being run on a 32-bit Windows system and mine being on a 64-bit Mac. When I run the Makefile by entering "ma
リリース、障害情報などのサービスのお知らせ
最新の人気エントリーの配信
処理を実行中です
j次のブックマーク
k前のブックマーク
lあとで読む
eコメント一覧を開く
oページを開く