# incrementally set environment; and keep a pad stack

use strict;
my @v;
$v[0] = do { my $x = 3; sub { $x; eval $_[0] } };  # set up closure

$v[0]( ' print "x=$x\n" ' );   # execute in this context level
print "sub=$v[0]\n";

$v[1] = $v[0]( ' do { my $y = 4; sub { $y; eval $_[0] } } ' );  # add a pad level

$v[1]( ' print "y=$y\n" ' );   # execute in this context level

$v[2] = $v[1]( ' do { my $z = 7; sub { $z; eval $_[0] } } ' );  # add a pad level

$v[2]( ' $y++ ' );   # execute in this context level
$v[2]( ' print "y=$y\n" ' );   # execute in this context level
$v[2]( ' print "done\n" ' );   # execute in this context level

__END__
use strict;
package Tied;
            sub TIESCALAR {
                my $class = shift;
                return bless { val => 42 }, $class;
            }
            sub FETCH {
                my $self = shift;
                print "FETCH\n";
                return $self->{val};
            }
package main;
use Data::Dumper;
	tie my $var, 'Tied';
print Dumper( $var );
	my $obj   = tied( $var );  # disable tie
print Dumper( $obj );
	my $alias = bless { %$obj }, ref $obj;  # must know what is the internal representation
__END__
	my $obj   = tied( $env{'$var'} );  # disable tie
	#my $alias = bless { %$obj }, ref $obj;  # must know what is the internal representation
	#my $var = tie $$obj, ...;

__END__

- label vars as: 
	our - with namespace
	my
	*
- store values in env
- compile begin-block
	with initializers:

	{ 
		my $var = $env{'$var'};
		our $module::var = $env{'$module::var'};
		# compiled block here

		# what happens if $var is tied?

		# save the side-effects
		$env{'$var'} = $var;
		$env{'$module::var'} = $module::var;

		# save the side-effects diff
		# in order to make the INIT block later
	}

- emit 
- eval

- what happens if $var is tied?
need to use a pointer instead of the actual var
or
all vars are replaced with $env{'...'}
- not a solution, because it's incompatible with p5 modules
xxx - but this may work:

	my $obj   = tied( $env{'$var'} );  # disable tie
	my $alias = bless { %$obj }, ref $obj;  # must know what is the internal representation
	my $var = tie $$obj, ...;

- just ignore tie for now?

- another option
- compile begin-block
	with initializers,
	and an eval:

	{ 
		my $var = $env{'$var'};
		our $module::var = $env{'$module::var'};
		# compiled block here

		# what happens if $var is tied?

		# save the side-effects
		$env{'$var'} = $var;
		$env{'$module::var'} = $module::var;

		# save the side-effects diff
		# in order to make the INIT block later

		return sub { eval $_[0] }	# eval in this context!
	}

my @v;
$v[0] =    sub { my $x = 3; sub { eval $_[0] } };
$v[1] = $v[0]( ' my $y = 4; sub { eval $_[0] } ' );
$v[2] = $v[0]( ' print "$x, $y\n"; sub { eval $_[0] } ' );