Re: private method

"Chas Owens" schreef:

Recently I was playing with something similar, when context-variables
were discussed on perl6.language:

#!/usr/bin/perl5 -l
use strict;
use warnings;

sub context {

sub bad_scope { $_[0] .q/->context, bad scope [/. $_[1] .q/]/ }

my $not_init = __PACKAGE__ .q/->context->{init}() not called yet/;
my $bad_init = q/no re-init allowed/;
my ($scope, $value);

{ id => \$scope,

init => sub {
if ($scope) {
$scope eq caller or die bad_scope $scope, caller;
die $bad_init;
$scope = caller;

set => sub {
$scope or die $not_init;
$scope eq caller or die bad_scope $scope, caller;
$value = $_[0];

get => sub {
$scope or die $not_init;
$scope eq caller or die bad_scope $scope, caller;
return $value;

my ($id, $init, $set, $get) = @{ context() }{ qw/id init set get/ };

print "id:$id";
print $get->() || q/<undef>/;

print $get->();

print $get->();

# { no strict 'refs';
# use Data::Dumper;
# print Dumper( \*{'main::'}{HASH} );
# }

print '------';

package Test;

# $set->('baz');
# print $get->();
# print '======';

my ($id1, $init1, $set1, $get1) = @{ main->context() }{ qw/id init set
get/ };

print "id1:$id1";
print $get1->() || q/<undef>/;

print $get1->();

print $get1->();

print $get1->();
print '======';


My next step was to add locking, but I got busy elsewhere.

See also: Scalar::Readonly, Readonly and Readonly::XS, attributes.

Affijn, Ruud

"Gewoon is een tijger."


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