小编arp*_*pho的帖子

我想编写一个函数来计算平均值,使用状态Monad in haskell这是我写的代码

import Control.Monad.State
type MyState = (Double,Double)
media s (a,n)= ((a*n+s)/(n+1),n+1)

getAverage:: Double ->State MyState  s1-> Double
getAverage s c=get >>= \s0 -> let (x,s1) =media s s0
            in put s1 >> return x

我在GHCI编译时遇到这个错误,我坚持在那里你可以帮我理解什么是错的,提前谢谢你

嗨,我的Xmonad一直工作到几天前,然后我想我用Synaptic安装了一些东西然后开始抱怨Xmonad.Config.Gnome这里是我的xmonad.hs

import XMonad
import XMonad.Config.Gnome


myManageHook = composeAll [
            (className =? "Pidgin" <&&> title =? "Buddy List") --> doFloat
           , (className =? "Gnome-panel" <&&> title =? "Run Application") --> doFloat
           -- , (className =? "XEyes") --> doShift "7"
           ]


main = xmonad $ gnomeConfig {
         modMask = mod4Mask
       , manageHook = myManageHook <+> manageHook gnomeConfig
       }

当我编译时,我得到这个:

ghc --make "xmonad.hs" (nella cartella: /home/giuseppe/.xmonad)
xmonad.hs:2:7:
Could not find module `XMonad.Config.Gnome':
  Use -v to see a list of the files searched for. …

我需要使用Python和pyRTF在RTF中生成一个文档,一切都很好:我对重音字母没有问题,它甚至接受欧元符号没有错误,但是€我得到了这个符号:¤.我用这种方式编码字符串:

x.encode("iso-8859-15")

我google了很多,但我无法解决这个问题,我需要做些什么来获得欧元符号？

我正在使用node.js和express开发一个简单的应用程序,几乎所有都可以,但是我得到了这个错误:

res.render("aggregatedCostList",{
      ^
TypeError: Object #<IncomingMessage> has no method 'render'
at /home/arpho/Projects/myBalance/routes/index.js:90:11
at /home/arpho/Projects/myBalance/node_modules/async/lib/async.js:116:25
at /home/arpho/Projects/myBalance/node_modules/async/lib/async.js:24:16
at /home/arpho/Projects/myBalance/routes/index.js:87:7
at /home/arpho/Projects/myBalance/node_modules/orientdb/lib/orientdb/db.js:539:24
at toRidsFromORIDsOfDocument (/home/arpho/Projects/myBalance/node_modules/orientdb/lib/orientdb/db.js:507:16)
at toRidsFromORIDsOfDocuments (/home/arpho/Projects/myBalance/node_modules/orientdb/lib/orientdb/db.js:534:9)
at Object.callback (/home/arpho/Projects/myBalance/node_modules/orientdb/lib/orientdb/db.js:302:9)
at EventEmitter.Manager.readResponse (/home/arpho/Projects/myBalance/node_modules/orientdb/lib/orientdb/connection/manager.js:218:21)
at Socket.<anonymous> (/home/arpho/Projects/myBalance/node_modules/orientdb/lib/orientdb/connection/manager.js:167:14)

当我在提交表单后尝试访问list_purchase时,它会在post和get中发生.

这是我的app.js的摘录:

      app.set('port', process.env.PORT || 3000);
  app.set('views', __dirname + '/views');
  app.set('view engine', 'jade');
  app.use(express.favicon());
  app.use(express.logger('dev'));
  app.use(express.bodyParser());
  app.use(express.methodOverride());
  app.use(express.cookieParser('your secret here'));
  app.use(express.session());
  app.use(app.router);
  app.use(express.static(path.join(__dirname, 'public')));
  //app.get('/new_post', routes.new_post_form);
  //app.post('/new_post', routes.new_post);
  app.get('/list_purchase',routes.list_purchase)
  app.post('/list_purchase',routes.filtered_list_purchase)

这是我的index.js的摘录:

  exports.filtered_list_purchase = function(res,req){
  debug('filtering')
  debug(req.req.body)
  range = req.req.body.range
  aggr = …

您好，在我的项目中，我需要可视化货币价值，就我的 f:convertNumber 而言

我使用固定的货币符号；一切都很好，但是当我尝试使用如下表达语言获取符号时：

<h:outputText value="#{rowItem.value}">
    <f:convertNumber currencySymbol="#{rowItem.getCurrencySymbol()}" groupingUsed="true" maxFractionDigits="2" type="currency" />
</h:outputText>

就像没有调用 getCurrencySymbol 方法一样，我确信我缺少一些东西。