#! user/bin/perl
use warnings;
use strict;

my @x = ( [1,1], [2,2], [3,3] );
my @y;

sub do_something {}

# this is what I want, but--- gets "syntax error ... near "$y["
#  foreach $y[0] (@x) {   <=== syntax error on this line
#    foreach $y[1] (@x) { 
#      do_something(@y);
#    }
#  }

# so, I use this method instead
foreach (@x) { $y[0] = $_;
  foreach (@x) { $y[1] = $_;
    do_something(@y);
  }
}