package Perl::Critic::Policy::References::ProhibitDoubleSigils;

use 5.010001;
use strict;
use warnings;
use Readonly;

use Perl::Critic::Utils qw{ :severities };
use parent 'Perl::Critic::Policy';

our $VERSION = '1.152';

#-----------------------------------------------------------------------------

Readonly::Scalar my $DESC => q{Double-sigil dereference};
Readonly::Scalar my $EXPL => [ 228 ];

#-----------------------------------------------------------------------------

sub supported_parameters { return ()                    }
sub default_severity     { return $SEVERITY_LOW         }
sub default_themes       { return qw(core pbp cosmetic) }
sub applies_to           { return 'PPI::Token::Cast'    }

#-----------------------------------------------------------------------------

sub violates {
    my ( $self, $elem, undef ) = @_;

    my $content = $elem->content();
    return if $content eq q{\\};
    return if $content =~ /[@ $ % * &] [*]/xms;
    return if $content eq q{$#*}; ## no critic (RequireInterpolationOfMetachars)

    my $sib = $elem->snext_sibling;
    return if !$sib;
    if ( ! $sib->isa('PPI::Structure::Block') && ! $sib->isa('PPI::Structure::Subscript') ) {
        return $self->violation( $DESC, $EXPL, $elem );
    }
    return; #ok!
}

1;

__END__

#-----------------------------------------------------------------------------

=pod

=head1 NAME

Perl::Critic::Policy::References::ProhibitDoubleSigils - Write C<@{ $array_ref }> instead of C<@$array_ref>.

=head1 AFFILIATION

This Policy is part of the core L<Perl::Critic|Perl::Critic>
distribution.


=head1 DESCRIPTION

When dereferencing a reference, put braces around the reference to
separate the sigils.  Especially for newbies, the braces eliminate any
potential confusion about the relative precedence of the sigils.

  push @$array_ref, 'foo', 'bar', 'baz';      #not ok
  push @{ $array_ref }, 'foo', 'bar', 'baz';  #ok

  foreach ( keys %$hash_ref ){}               #not ok
  foreach ( keys %{ $hash_ref } ){}           #ok


=head1 CONFIGURATION

This Policy is not configurable except for the standard options.


=head1 AUTHOR

Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>

=head1 COPYRIGHT

Copyright (c) 2005-2023 Imaginative Software Systems.  All rights reserved.

This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.  The full text of this license
can be found in the LICENSE file included with this module.

=cut

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