From peter@schwenn.com

(Please feel free to move this to perl6-users if you feel that more
appropriate.)

The code below gives the interaction​:

(Seeming to suggest some fault in the Class/Object handling; but of
course COULD be a simple programming misconception/bug)

C​:\parrot>perl6 /peter/perlprograms/lilcalc.p6
8 [ 8 key struck ]
Read token 8
pushed 8 to @​items 8 at depth 0 [ ok so far  ]
3 [ 3 key struck ]
Read token 3
pushed 3 to @​items 3 3 at depth 1 [ @​items should be 8 3 not 3 3 ]
* [ * key struck ]
Read token *
popping from @​items * * at depth 1 , [ similarly, @​items should be 8 3 not * *]
 the item​: *
popping from @​items * * at depth 0 ,
 the item​: *
....
This program works properly if I code the pushing and popping of
@​items inline - no Classes/Objects. And it fails in the same way if I
use the forms "@​items.pop" and "@​items.push" instead of the form
"@​items[$depth]" .

--------------------------------------------------------------------start
code---------------------------------------------------
#!perl6

class OpStack
{
has Int $depth= -1;
has @​items;
method popp {
my $popd;
say "popping from \@​items {@​items[]} at depth $depth ,";
$popd= @​items[$depth--]; # " =@​items.pop" fails in same way]
say " the item​: $popd \n";
return $popd;
  }
method pushh($arhg) {
@​items[++$depth]= $arhg;
say "pushed $arhg to \@​items {@​items[]} at depth $depth \n";
  }
}

class Tokens { #no particular reason (yet) why Tokens is a Class
method next {
  my $Toke= =$*IN;
  say "Read token $Toke\n";
  return $Toke;
  }
}

sub calc()
{
my Tokens $Token .= new;
my OpStack $Stack .= new;
my $first;
my $second;
my $answer;
my $tok;
my $toktype;

loop {

$tok= $Token.next;
$toktype= lex($tok);

given $toktype {
  when /arg/ { $Stack.pushh($tok); }
  when /op$|opbinary/ {
  $second= $Stack.popp;
  $first= $Stack.popp;
  $answer= eval ($first, $tok, $second);
  say "$first $tok $second = $answer\n";
  $Stack.pushh($answer); }
default { say "err\n"; } #later​: single arg ops
} # given
} # loop forever
} # calc

calc;
exit 1;

sub lex ($token)
{
given $token {
when / <[A..Z]> (\d) / {return $0;} ###operation not defined yet
when / <[0..9\.]>+ / {return "arg";}
when / <[+\-]>? \d+ .? \d? <[ED]>? <[+\-]>? \d? / {return "arg";}
#could be a better regex
when / <[+\-*/^%]> / {return "opbinary";}
when / (push|pop) / {return "memop";}
### need logic for opunary (which could be e.g. error code on $second=
...pop [only $first was there])
default {return "err";}
  }
}

-----------------------------------------------end code

From @moritz

I can't find a bug report in here, so I reject this ticket.

@moritz - Status changed from 'new' to 'rejected'