Scala programming mystery -


i expecting below program print each character of string "this test" on seperate line , when run snippet on scalafiddle.io , not print , can please me find why ?

    abstract class absiterator{       type t       def hasnext:boolean       def next():t     }      class stringiterator(s:string) extends absiterator{       type t = char       private var = 0       def hasnext = < s.length        def next()={         val ch = s charat         += 1         ch       }     }      trait richiterator extends absiterator{         def foreach (f:t => unit):unit = while(hasnext) f(next())       }      object stringiteratortest extends app{      class iter extends stringiterator ("this test") richiterator       val iter = new iter       iter foreach println     }

since said tried on scalafiddle, not executing inside main method.

println("as script - executed")  object x extends app  {   println("as main app - not executed") }

you need run script below, working scalafiddle code here - https://scalafiddle.io/sf/3czsxsp/0

abstract class absiterator{   type t   def hasnext:boolean   def next():t }  class stringiterator(s:string) extends absiterator{   type t = char   private var = 0   def hasnext = < s.length    def next(): t = {     val ch = s charat     += 1     ch   } }  trait richiterator extends absiterator{   def foreach (f:t => unit):unit = while(hasnext) f(next()) }  class iter extends stringiterator ("this test") richiterator val iter = new iter iter foreach println

output

t h s  s   t e s t

code - https://scastie.scala-lang.org/prayagupd/upw6piqtrpenlxor4wdlsw


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