Default arguments to Scala's main function? -


how work, i've tried , without new keyword:

object main extends app {     override def main (args : array[string] = new array("default argument")) {         println("args(0) = " + args(0))     } }

http://ideone.com/5aytxy (i have tried other [1, 2] methods think val causing issues)

docs: http://docs.scala-lang.org/sips/completed/named-and-default-arguments.html#default_arguments

ps: should confirm want bound args name; rather var or val. additionally scope needs global within main.

to satisfy intent here (as clarified last comment @alexiv's answer) - keeping field name of args while allowing default value field - can override field, using reference original value prefixed super.:

object main extends app {     override val args: array[string] = if (super.args.isempty) array("default argument") else super.args     println("args(0) = " + args(0)) }

Comments

Post a Comment

Popular posts from this blog

php - Add the correct number of days for each month -

using following function can display years , months between 2 dates, how can add correct days each month array within each month? can't add days manually need account leap years etc. function yearmonth($start_date, $end_date) { $begin = new datetime( $start_date ); $end = new datetime( $end_date); $interval = new dateinterval('p1m'); // 1 month interval $period = new dateperiod($begin, $interval, $end); foreach ( $period $dt ) $years[$dt->format( "y" )][] = $dt->format( "f" ); return $years; } $list = yearmonth("2007-03-24", "2009-06-26"); var_dump($list); since nobody else answered: function yearmonth($start_date, $end_date) { $begin = new datetime( $start_date ); $end = new datetime( $end_date); $interval = new dateinterval('p1d'); // 1 month interval $period = new dateperiod($begin, $interval, $end); $lastmonth = null; $lastyear = null; $aresult = array(); forea...
Read more

java.util.scanner - How to read and add only numbers to array from a text file -

i'm learning java , have question regarding reading file want read numbers file contains strings well. here example of file: 66.56 "3 java 3-43 5-42 2.1 1 and here coding: public class test { public static void main (string [] args){ if (0 < args.length) { file x = new file(args[0]); try{ scanner in = new scanner( new fileinputstream(x)); arraylist<double> test = new arraylist<>(); while(in.hasnext()){ if(in.hasnextdouble()){ double f=in.nextdouble(); test.add(f);} else {in.next();} } catch(ioexception e) { system.err.println("exception during reading: " + e); } } my problem add 66.56,2.1 , 1 doesn't add 3 after "3 or ignores 3-43 , 5-42 can tell me how skip strings , add doubles here? thanks all said 3 ie; "3, 3-43 , 4-42 strings either u read string , split , check number @ " , - or put in space between characters , integers. jvm after compilation tre...
Read more