NAME

Devel::Declare -

SYNOPSIS

  use Devel::Declare ();
  use Scope::Guard;
  
  {
    package MethodHandlers;
  
    use strict;
    use warnings;
  
    our ($Declarator, $Offset);
  
    sub skip_declarator {
      $Offset += Devel::Declare::toke_move_past_token($Offset);
    }
  
    sub skipspace {
      $Offset += Devel::Declare::toke_skipspace($Offset);
    }
  
    sub strip_name {
      skipspace;
      if (my $len = Devel::Declare::toke_scan_word($Offset, 1)) {
        my $linestr = Devel::Declare::get_linestr();
        my $name = substr($linestr, $Offset, $len);
        substr($linestr, $Offset, $len) = '';
        Devel::Declare::set_linestr($linestr);
        return $name;
      }
      return;
    }
  
    sub strip_proto {
      skipspace;
      
      my $linestr = Devel::Declare::get_linestr();
      if (substr($linestr, $Offset, 1) eq '(') {
        my $length = Devel::Declare::toke_scan_str($Offset);
        my $proto = Devel::Declare::get_lex_stuff();
        Devel::Declare::clear_lex_stuff();
        $linestr = Devel::Declare::get_linestr();
        substr($linestr, $Offset, $length) = '';
        Devel::Declare::set_linestr($linestr);
        return $proto;
      }
      return;
    }
  
    sub shadow {
      my $pack = Devel::Declare::get_curstash_name;
      Devel::Declare::shadow_sub("${pack}::${Declarator}", $_[0]);
    }
  
    # undef  -> my ($self) = shift;
    # ''     -> my ($self) = @_;
    # '$foo' -> my ($self, $foo) = @_;
  
    sub make_proto_unwrap {
      my ($proto) = @_;
      my $inject = 'my ($self';
      if (defined $proto) {
        $inject .= ", $proto" if length($proto);
        $inject .= ') = @_; ';
      } else {
        $inject .= ') = shift;';
      }
      return $inject;
    }
  
    sub inject_if_block {
      my $inject = shift;
      skipspace;
      my $linestr = Devel::Declare::get_linestr;
      if (substr($linestr, $Offset, 1) eq '{') {
        substr($linestr, $Offset+1, 0) = $inject;
        Devel::Declare::set_linestr($linestr);
      }
    }

    sub scope_injector_call {
      return ' BEGIN { MethodHandlers::inject_scope }; ';
    }
  
    sub parser {
      local ($Declarator, $Offset) = @_;
      skip_declarator;
      my $name = strip_name;
      my $proto = strip_proto;
      my $inject = make_proto_unwrap($proto);
      if (defined $name) {
        $inject = scope_injector_call().$inject;
      }
      inject_if_block($inject);
      if (defined $name) {
        $name = join('::', Devel::Declare::get_curstash_name(), $name)
          unless ($name =~ /::/);
        shadow(sub (&) { no strict 'refs'; *{$name} = shift; });
      } else {
        shadow(sub (&) { shift });
      }
    }
  
    sub inject_scope {
      $^H |= 0x120000;
      $^H{DD_METHODHANDLERS} = Scope::Guard->new(sub {
        my $linestr = Devel::Declare::get_linestr;
        my $offset = Devel::Declare::get_linestr_offset;
        substr($linestr, $offset, 0) = ';';
        Devel::Declare::set_linestr($linestr);
      });
    }
  }
  
  my ($test_method1, $test_method2, @test_list);
  
  {
    package DeclareTest;
  
    sub method (&);
  
    BEGIN {
      Devel::Declare->setup_for(
        __PACKAGE__,
        { method => { const => \&MethodHandlers::parser } }
      );
    }
  
    method new {
      my $class = ref $self || $self;
      return bless({ @_ }, $class);
    }
  
    method foo ($foo) {
      return (ref $self).': Foo: '.$foo;
    }
  
    method upgrade(){ # no spaces to make case pathological
      bless($self, 'DeclareTest2');
    }
  
    method DeclareTest2::bar () {
      return 'DeclareTest2: bar';
    }
  
    $test_method1 = method {
      return join(', ', $self->{attr}, $_[1]);
    };
  
    $test_method2 = method ($what) {
      return join(', ', ref $self, $what);
    };
  
    method main () { return "main"; }
  
    @test_list = (method { 1 }, sub { 2 }, method () { 3 }, sub { 4 });
  
  }
  
  use Test::More 'no_plan';
  
  my $o = DeclareTest->new(attr => "value");
  
  isa_ok($o, 'DeclareTest');
  
  is($o->{attr}, 'value', '@_ args ok');
  
  is($o->foo('yay'), 'DeclareTest: Foo: yay', 'method with argument ok');
  
  is($o->main, 'main', 'declaration of package named method ok');
  
  $o->upgrade;
  
  isa_ok($o, 'DeclareTest2');
  
  is($o->bar, 'DeclareTest2: bar', 'absolute method declaration ok');
  
  is($o->$test_method1('no', 'yes'), 'value, yes', 'anon method with @_ ok');
  
  is($o->$test_method2('this'), 'DeclareTest2, this', 'anon method with proto ok');
  
  is_deeply([ map { $_->() } @test_list ], [ 1, 2, 3, 4], 'binding ok');

(this is t/method-no-semi.t in this distribution)

DESCRIPTION

setup_for

  Devel::Declare->setup_for(
    $package,
    {
      $name => { $op_type => $sub }
    }
  );

Currently valid op types: 'check', 'rv2cv'

AUTHOR

Matt S Trout - <mst@shadowcat.co.uk>

Company: http://www.shadowcat.co.uk/ Blog: http://chainsawblues.vox.com/

LICENSE

This library is free software under the same terms as perl itself