Scala case class instantiate when you have not-used-in-equals properties -


have academic class:

case class a3(name: string)(val s: string) {}

trying instantiate it. tried

  1. val v = a3("la")
  2. val v = a3("la", "ba")

neither worked. looked @ book, http://techbus.safaribooksonline.com/book/programming/scala/9780981531687/case-classes-and-pattern-matching/case_classes_and_pattern_matching_html

i googled not answer.

scala ide messages did not (correction : do, tool tip box not big enough , had black background, missed important part, see below repl output). repl helped, need use 2 sets of parenthesis like:

val v = a3("ga")("mu")

full repl:

scala> case class a3(name: string)(var s : string) {} defined class a3

scala> val v3 = a3("a2") :13: error: missing argument list method apply in object a3 unapplied methods converted functions when function type expected. can make conversion explicit writing apply _ or apply(_)(_) instead of apply. val v3 = a3("a2") ^

scala> val v3 = a3("a2")("s") v3: a3 = a3(a2)


Comments

Post a Comment

Popular posts from this blog

asynchronous - C# WinSCP .NET assembly: How to upload multiple files asynchronously -

i using winscp .net assembly uploading files. want upload multiple files asynchronous way. have created method works single upload. public class uploadingdata { private sessionoptions _sessionoptions; private session _session; //connection etc private void onconnected() { foreach (var fileinfo in localfileslist) { var task = task.factory.startnew(() => uploadfilesasync(fileinfo)); } } private async task uploadfilesasync(string file) { string remotefilepath = _session.translatelocalpathtoremote(file, @"/", "/test_data_upload"); var uploading = _session.putfiles(file, remotefilepath, false); //when done await task.run(() => thread.sleep(1000)); } } please suggest me correct way. thanks you can use backgroundworker class this: string[] images = new string[50]; foreach (var path in images) { backgroundworker
Read more

aws api gateway - SerializationException in posting new Records via Dynamodb Proxy Service in API -

i getting "__type": "com.amazon.coral.service#serializationexception" as reply in postman & in test console in api gateway trying post record directly dynamodb using api proxy services.. referring aws article - https://aws.amazon.com/blogs/compute/using-amazon-api-gateway-as-a-proxy-for-dynamodb/ here's mapping { "tablename": "tablenamegoeshere", "item": { "id" : "$context.requestid" "eventname" : "$input.path('$.eventname')", "timestamp" : $input.path('$.timestamp'), "answers": "$util.parsejson($input.path('$.answers'))" } } update: did asked ... , worked if try add array of json objects gives me above same error - here's trying now. please - couldnt find on google well #set($inputroot = $input.path('$')) { "tablename": "answer", "item": {
Read more

asp.net - Problems sending emails from forum -

i have been redesigning site has message board, has been written guy looked after site. it has few problems , written in .asp , uses .mdb files database. you can see whole thing here . feel free post if helps, test thing have set using original files , new database. the basic problem when posts message, supposed email sent them, have posted it. when replies, originator supposed message, replier has been posted. i’d have thought @ point in process there should script/file in postmessage.asp? the postmessage.asp page below. <% option explicit %> <!-- #include virtual="common/adovbs.inc" --> <html> <head> <meta http-equiv="content-type" content="text/html; charset=windows-1252"> <meta name="generator" content="microsoft frontpage 4.0"> <meta name="progid" content="frontpage.editor.document"> <title>new page 2</title> <base target="_self"
Read more