Seems like the
method display as written would actually print all the cells in one row --
method iterate doesn't have an explicit hook for "reached end of line". That's fine, since we have
$.max available within the object.
I think method display should actually look like this:
method display
{
iterate
{
print $.grid[$^x][$^y] ?? '+' :: '.';
print "\n" if ($^x == $.max);
# print each row on own line
}
print "\n"; # blank line follows grid
print "Turn $(++$.count), press enter to continue"
print " or ctl-c to quit";
<$*IN>;
.calculate();
} # end method display
A separate style comment: wouldn't it be a bit cleaner to remove the .calculate(); line from method display and change the loop at the top so that it reads:
loop { $life.display(); $life.calculate(); }
Then there's no nasty surprise when someone does:
# somewhere far, far, away
$life.display;
`shell-script;clear`; # weird stuff on screen tty
$life.display; # refresh terminal *only*
later. I recognize that's personal preference, but Side Effects Are Scary.