X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=moose-class%2Fslides%2Findex.html;h=70bdfc651c96000d181fa3e1664ae8a5fe5a06b6;hb=c1d605dbbaf56eed6436ec8821158c509b8210fe;hp=10d0339e76129eee80f2d3b93fd3046f9deef440;hpb=ddd87d751a8c055d95240d6af73109770c743466;p=gitmo%2Fmoose-presentations.git diff --git a/moose-class/slides/index.html b/moose-class/slides/index.html index 10d0339..70bdfc6 100644 --- a/moose-class/slides/index.html +++ b/moose-class/slides/index.html @@ -1,10 +1,10 @@ - + Introduction to Moose + @@ -39,6 +39,11 @@ img#me05 {top: 43px;left: 36px;}
@@ -47,7 +52,17 @@ img#me05 {top: 43px;left: 36px;}

Introduction to Moose

-

YAPC 2009

+

git://git.moose.perl.org/moose-presentations.git

+
+ +
+

Introduce Yourselves

+ +
@@ -56,20 +71,25 @@ img#me05 {top: 43px;left: 36px;}
-

Concepts

+

Moose Background

+
+

Part 0: Moose Concepts

+
+

Classes

@@ -116,7 +136,7 @@ img#me05 {top: 43px;left: 36px;}
  • Attributes have ...
    • @@ -204,7 +224,7 @@ use Moose;
    -

    Before & After

    +

    Before and After

    before 'foo'
     => sub { warn 'About to call foo()' };
@@ -225,7 +245,10 @@ after  'foo'
     my @return =
         $self->$real_foo( @_, bar => 42 );
 
-    return ( @return, 'modify return values' );
+    return (
+        @return,
+        'modify return values'
+    );
 };
    @@ -246,7 +269,10 @@ after 'foo' 
    package Person;
 use Moose;
 
-has 'weight' => ( is => 'ro', isa => 'Int' );
+has weight => (
+    is  => 'ro',
+    isa => 'Int',
+);
 
 # kaboom
 Person->new( weight => 'fat' );
    @@ -268,14 +294,14 @@ Person->new( weight => 'fat' ); 
    package Person;
 use Moose;
 
-has 'blog_uri' => (
+has blog_uri => (
     is      => 'rw',
     isa     => 'URI',
-    handles => { 'blog_hostname' => 'host' },
+    handles => { 'blog_host' => 'host' },
 );
 
-$person->blog_hostname;
-# really calls $person->blog_uri->host
+$person->blog_host;
+# really calls $person->blog_uri->host
    @@ -328,7 +354,7 @@ has 'blog_uri' => (

    Why Moose?

    @@ -801,7 +827,7 @@ sub last_name {

    Typo?

    - $self->{last_nane} + $self->{last_nane}
    @@ -817,7 +843,7 @@ has last_name => (
    -

    Moose Classes

    +

    Part 1: Moose Classes

    @@ -853,10 +879,103 @@ use Moose;
    +

    BUILDARGS

    + + +
    + +
    +

    BUILDARGS Example

    + + 
    package Person;
+use Moose;
+
+sub BUILDARGS {
+    my $class = shift;
+
+    if ( @_ == 1 && ! ref $_[0] ) {
+        return { ssn => $_[0] };
+    }
+    return $class->SUPER::BUILDARGS(@_);
+}
+
+Person->new('123-45-6789')
    +
    + +
    +

    BUILD

    + + +
    + +
    +

    BUILD Example

    + + 
    package Person;
+use Moose;
+
+sub BUILD {
+    my $self = shift;
+
+    if ( $self->country_of_residence
+         eq 'USA' ) {
+        die 'All US residents'
+            . ' must have an SSN'
+            unless $self->has_ssn;
+    }
+}
    +
    + +
    +

    Object Construction a la Moose

    + + 
    Person->new(@_)
    + +
      +
    1. Calls Person->BUILDARGS(@_) to turn @_ into a hashref
      2. +
    2. Blesses a reference
      3. +
    3. Populates attributes based on the hashref from #1
      4. +
    4. Calls $new_object->BUILDALL($constructor_args) +
      ... which calls all BUILD methods
      5. +
    5. Returns the object
      6. +
    +
    + +
    +

    The Object is Opaque

    + + +
    + +
    +

    DEMOLISH

    + + +
    + +

    extends

    package Employee;
@@ -871,18 +990,18 @@ use Moose;
     
  • Each call to extends resets your parents
    • 
   
 
-  
    WRONG
    
+  
    Wrong
    
 
   
    package EvilEmployee;
 use Moose;
 extends 'Person';
-extends 'Thief';
    
+extends 'Thief';
    -

    RIGHT

    +

    Right

    package EvilEmployee;
 use Moose;
-extends 'Person', 'Thief';
    +extends 'Person', 'Thief';
    @@ -890,7 +1009,7 @@ extends 'Person', 'Thief'; 
    package My::LWP;
 use Moose;
-extends 'LWP';
    +extends 'LWP';
    -

    overrides and super

    +

    override and super

    -

    overrides and super

    +

    override and super

    package Employee;
 use Moose;
 
-extends 'Person';
+extends 'Person';
 
-overrides work => sub {
+override work => sub {
     my $self = shift;
 
-    die "Pay me first" unless $self->got_paid;
+    die "Pay me first"
+        unless $self->got_paid;
     super();
 };
    +

    Caveat super

    @@ -939,7 +1060,7 @@ use Moose;
    -

    Attributes (Part 1)

    +

    Minimal Attributes

    @@ -1060,15 +1182,2583 @@ use Moose;
    -

    Classes - Exercises

    +

    Classes Summary

    + + +
    + +
    +

    Questions?

    +
    - 
    $ cd exercises
-$ prove -lv t/00-prereq.t
+
    
+  
    Exercises
    
 
-Missing anything? Install it. (see tarballs/)
+  
    # cd exercises
 
-# prove -lv t/01-classes.t
-# 
+# perl bin/prove -lv t/00-prereq.t
 
-
-
+# perl install-moose (if needed)
+
+# perl bin/prove -lv t/01-classes.t
+
+# edit lib/Person.pm and lib/Employee.pm
+
+Iterate til this passes all its tests
    
+
    
+
+
    
+  
    Part 2: Roles
    
+
    
+
+
    
+  
    Just What Is a Role?
    
+
+  
+
    
+
+
    
+  
    Roles - State and Behavior
    
+
+  
    package HasPermissions;
+use Moose::Role;
+# state
+has access_level => ( is => 'rw' );
+
+# behavior
+sub can_access {
+    my $self     = shift;
+    my $required = shift;
+
+    return $self->access_level
+             >= $required;
+}
    
+
+
    
+
+
    
+  
    Roles Can Define Interfaces
    
+
+  
    package Printable;
+use Moose::Role;
+
+requires 'as_string';
    
+
    
+
+
    
+  
    Roles Can Do All Three
    
+
+  
    package Printable;
+use Moose::Role;
+
+requires 'as_string';
+
+has has_been_printed => ( is => 'rw'  );
+
+sub print {
+    my $self = shift;
+    print $self->as_string;
+    $self->has_been_printed(1);
+}
    
+
    
+
+
    
+  
    Classes Consume Roles
    
+
+  
    package Person;
+use Moose;
+
+with 'HasPermissions';
    
+
    
+
+
    
+  
    Classes Consume Roles
    
+
+
    my $person = Person->new(
+    first_name   => 'Kenichi',
+    last_name    => 'Asai',
+    access_level => 42,
+);
+
+print $person->full_name
+    . ' has '
+    . $person->can_access(42)
+        ? 'great power'
+        : 'little power';
    
+
    
+
+
    
+  
    Roles in Practice
    
+
+  
+
    
+
+
    
+  
    In Other Words ...
    
+
+
    package Person;
+use Moose;
+
+with 'Printable';
    
+
    
+
+
    
+  
    In Other Words ...
    
+
+
    package Person;
+use Moose;
+
+with 'Printable';
+
+has has_been_printed => ( is => 'rw'  );
+
+sub print {
+    my $self = shift;
+    print $self->as_string;
+    $self->has_been_printed(1);
+}
    
+
    
+
+
    
+  
    Except
    
+
+  
+
+  
    if ( Person->does('Printable') ) { ... }
+
+# or ...
+
+Person->meta->does('Printable')
    
+
+
    
+
+
    
+  
    These Names Are the Same
    
+
+  
+
    
+
+
    
+  
    Conflicts Between Roles
    
+
+  
+
    
+
+
    
+  
    Conflict Example
    
+
+  
    package IsFragile;
+use Moose::Role;
+
+sub break { ... }
+
+package CanBreakdance;
+use Moose::Role;
+
+sub break { ... }
    
+
    
+
+
    
+  
    Conflict Example
    
+
+  
    package FragileDancer;
+use Moose;
+
+with 'IsFragile', 'CanBreakdance';
    
+
+  
+
    
+
+
    
+  
    Conflict Resolution
    
+
+  
+
    
+
+
    
+  
    Method Aliasing
    
+
+  
    package FragileDancer;
+use Moose;
+
+with 'IsFragile' =>
+         { -alias =>
+               { break => 'break_bone' } },
+     'CanBreakdance' =>
+         { -alias =>
+               { break => 'break_it_down' } };
    
+
+  
+
    
+
+
    
+  
    Method Exclusion
    
+
+  
    package FragileDancer;
+use Moose;
+
+with 'IsFragile' =>
+         { -alias =>
+               { break => 'break_bone' },
+           -excludes => 'break' },
+     'CanBreakdance' =>
+         { -alias =>
+               { break => 'break_it_down' },
+           -excludes => 'break' };
    
+
    
+
+
    
+  
    And then ...
    
+
+  
    package FragileDancer;
+use Moose;
+
+sub break {
+    my $self = shift;
+
+    $self->break_it_down;
+    if ( rand(1) < 0.5 ) {
+        $self->break_bone;
+    }
+}
    
+
    
+
+
    
+  
    Still Full of Fail
    
+
+  
+
    
+
+
    
+  
    Hot Role-on-Role Action
    
+
+  
    package Comparable;
+use Moose::Role;
+
+requires 'compare';
    
+
    
+
+
    
+  
    Hot Role-on-Role Action
    
+
+  
    package TestsEquality;
+use Moose::Role;
+
+with 'Comparable';
+
+sub is_equal {
+    my $self = shift;
+    return $self->compare(@_) == 0;
+}
    
+
    
+
+
    
+  
    And then ...
    
+
+  
    package Integer;
+use Moose;
+
+with 'TestsEquality';
+
+# Satisfies the Comparable role
+sub compare { ... }
+
+Integer->does('TestsEquality'); # true
+Integer->does('Comparable'); # also true!
    
+
    
+
+
    
+  
    Name Conflicts Between Roles
    
+
+  
    package HasSubProcess;
+use Moose::Role;
+
+sub execute { ... }
+
+package Killer;
+use Moose::Role;
+
+with 'HasSubProcess';
+
+sub execute { ... }
    
+
    
+
+
    
+  
    Delayed Conflict
    
+
+  
    package StateOfTexas;
+with 'Killer';
    
+
+  
+
    
+
+
    
+  
    Roles as Interfaces
    
+
+  
+
    
+
+
    
+  
    The Attribute Gotcha
    
+
+
    package HasSize;
+use Moose::Role;
+
+requires 'size';
+
+package Shirt;
+use Moose;
+
+with 'HasSize';
+
+has size => ( is => 'ro' );
    
+
    
+
+
    
+  
    The Attribute Gotcha Workaround
    
+
+  
    package HasSize;
+use Moose::Role;
+
+requires 'size';
+
+package Shirt;
+use Moose;
+
+has size => ( is => 'ro' );
+
+with 'HasSize';
    
+
    
+
+
    
+  
    Compile-time Is a Lie
    
+
+  
+
    
+
+
    
+  
    Enforcing Roles
    
+
+  
    package Comparison;
+use Moose;
+
+has [ 'left', 'right' ] => (
+    is   => 'ro',
+    does => 'Comparable',
+);
+
    
+
+  
+
    
+
+
+
    
+  
    Roles Can Be Applied to Objects
    
+
+  
    use Moose::Util qw( apply_all_roles );
+
+my $fragile_person = Person->new( ... );
+apply_all_roles( $fragile_person,
+                 'IsFragile' );
    
+
+  
+
    
+
+
    
+  
    Roles Are Dirty Too
    
+
+  
+
+  
    package Comparable;
+use Moose::Role;
+
+requires 'compare';
+
+no Moose::Role;
    
+
+  
+
    
+
+
    
+  
    The Zen of Roles
    
+
+  
+
    
+
+
    
+  
    Abstract Examples
    
+
+  
+
    
+
+
    
+  
    Real Examples
    
+
+  
+
    
+
+
    
+  
    Real Examples
    
+
+  
+
    
+
+
    
+  
    Roles Summary
    
+
+  
+
    
+
+
    
+  
    Questions?
    
+
      
+
+
    
+  
    Exercises
    
+
+  
    # cd exercises
+# perl bin/prove -lv t/02-roles.t
+
+Iterate til this passes all its tests
    
+
    
+
+
    
+  
    Part 3: Basic Attributes
    
+
    
+
+
    
+  
    Attributes Are Huge
    
+
+  
+
    
+
+
    
+  
    Quick Review
    
+
+  
+
+  
    package Shirt;
+use Moose;
+
+has 'color'     => ( is => 'ro' );
+has 'is_ripped' => ( is => 'rw' );
    
+
    
+
+
    
+  
    Required-ness
    
+
+  
+
    
+
+
    
+  
    Required-ness
    
+
+  
    package Person;
+use Moose;
+
+has first_name => (
+    is       => 'ro',
+    required => 1,
+);
+
+Person->new( first_name => undef ); # ok
+Person->new(); # kaboom
    
+
    
+
+
    
+  
    Default and Builder
    
+
+  
+
    
+
+
    
+  
    Default
    
+
+  
+
+  
    package Person;
+use Moose;
+
+has bank => (
+    is      => 'rw',
+    default => 'Spire FCU',
+);
    
+
    
+
+
    
+  
    Default
    
+
+  
+
+  
    package Person;
+use Moose;
+
+has bank => (
+    is      => 'rw',
+    default =>
+        sub { Bank->new(
+                  name => 'Spire FCU' ) },
+);
    
+
    
+
+
    
+  
    Subroutine Reference Default
    
+
+  
+
    
+
+
    
+  
    Why No Other Reference Types?
    
+
+  
    package Person;
+use Moose;
+
+has bank => (
+    is      => 'rw',
+    default => Bank->new(
+                   name => 'Spire FCU' ),
+);
    
+
+  
+
    
+
+
    
+     
    Defaulting to an Empty Reference
    
+
+  
    package Person;
+use Moose;
+
+has packages => (
+    is      => 'rw',
+    default => sub { [] },
+);
    
+
    
+
+
    
+  
    What if I Want to Share?
    
+
+  
    package Person;
+use Moose;
+
+my $highlander_bank =
+    Bank->new( name => 'Spire FCU' );
+
+has bank => (
+    is      => 'rw',
+    default => sub { $highlander_bank },
+);
    
+
    
+
+
    
+  
    Builder
    
+
+  
+
    
+
+
    
+  
    Builder
    
+
+  
    package Person;
+use Moose;
+
+has bank => (
+    is      => 'rw',
+    builder => '_build_bank',
+);
+
+sub _build_bank {
+    my $self = shift;
+    return Bank->new(
+        name => 'Spire FCU' );
+}
    
+
    
+
+
    
+  
    Default vs Builder
    
+
+  
+
    
+
+
    
+  
    Builder Bonuses
    
+
+  
+
    
+      
+
    
+  
    Role Requires Builder
    
+
+  
    package HasBank;
+use Moose::Role;
+
+requires '_build_bank';
+
+has bank => (
+    is      => 'ro',
+    builder => '_build_bank',
+);
    
+
    
+
+
    
+  
    Lazy, Good for Nothin' Attributes
    
+
+  
+
    
+
+
    
+  
    The Power of Dynamic Defaults
    
+
+  
    package Person;
+use Moose;
+
+has shoe_size => (
+    is => 'ro',
+);
    
+
    
+
+
    
+  
    The Power of Dynamic Defaults
    
+
+  
    has shoes => (
+    is      => 'ro',
+    lazy    => 1,
+    builder => '_build_shoes',
+);
+
+sub _build_shoes {
+    my $self = shift;
+
+    return Shoes->new(
+        size => $self->shoe_size );
+}
    
+
    
+
+
    
+  
    Lazy is Good
    
+
+  
+
        
+
+
    
+  
    Clearer and Predicate
    
+
+  
+
    
+
+
    
+  
    Clearer and Predicate
    
+
+  
    package Person;
+use Moose;
+
+has account => (
+    is        => 'ro',
+    lazy      => 1,
+    builder   => '_build_account',
+    clearer   => '_clear_account',
+    predicate => 'has_account',
+);
    
+
    
+
+
    
+  
    Clearer and Lazy Defaults
    
+
+  
+
    
+
+
    
+  
    Renaming constructor arguments
    
+
+  
+
    
+
+
    
+  
    Some init_arg examples
    
+
+  
    package Person;
+use Moose;
+
+has shoe_size => (
+    is       => 'ro',
+    init_arg => 'foot_size',
+);
+
+Person->new( shoe_size => 13 );
+
+my $person =
+    Person->new( foot_size => 13 );
+print $person->shoe_size;
    
+
    
+
+
    
+  
    Some init_arg examples
    
+
+
    package Person;
+use Moose;
+
+has shoes => (
+    is       => 'ro',
+    init_arg => undef,
+);
+
+Person->new( shoes => Shoes->new );
    
+
    
+
+
    
+  
    Why Set init_arg => undef?
    
+
+  
+
    
+
+
    
+  
    Attribute Inheritance
    
+
+  
+
       
+
+
    
+  
    Attribute Inheritance Example
    
+
+  
    package Employee;
+use Moose;
+
+extends 'Person';
+
+has '+first_name' => (
+    default => 'Joe',
+);
    
+
    
+
+
    
+  
    Attribute Inheritance Warning
    
+
+  
+
    
+
+
    
+  
    Changing Accessor Names
    
+
+  
    package Person;
+use Moose;
+
+has first_name => (
+    accessor => 'first_name',
+);
    
+
+  
+
    
+
+
    
+  
    Changing Accessor Names
    
+
+  
    package Person;
+use Moose;
+
+has first_name => (
+    reader => 'first_name',
+    writer => undef,
+);
    
+
+  
+
    
+
+
+
    
+  
    Changing Accessor Names
    
+
+  
    package Person;
+use Moose;
+
+has first_name => (
+    reader => 'get_first_name',
+    writer => 'set_first_name',
+);
    
+
    
+
+
    
+  
    Changing Accessor Names
    
+
+  
    package Person;
+use Moose;
+
+has first_name => (
+    is     => 'rw',
+    writer => '_first_name',
+);
    
+
+  
+
    
+
+
    
+  
    ETOOMUCHTYPING
    
+
+  
+
    
+
+
    
+  
    ETOOMUCHTYPING
    
+
+  
    package Person;
+use Moose;
+use MooseX::SemiAffordanceAccessor;
+
+has first_name => (
+    is => 'rw',
+);
    
+
+  
+
    
+
+
    
+  
    Basic Attributes Summary
    
+
+  
+
    
+
+
    
+  
    Questions?
    
+
      
+
+
    
+  
    Exercises
    
+
+  
    # cd exercises
+# perl bin/prove -lv \
+      t/03-basic-attributes.t
+
+Iterate til this passes all its tests
    
+
    
+
+
    
+  
    Part 4: Method Modifiers
    
+
    
+
+
    
+  
    What is a Method Modifier
    
+
+  
+
    
+
+
    
+  
    What is a Method Modifier
    
+
+  
+
    
+
+
    
+  
    Before and After
    
+
+  
+
    
+
+
    
+  
    Uses for before
    
+
+  
+
+  
    package Person;
+use Moose;
+
+before work => sub {
+    my $self = shift;
+    die 'I have no job!'
+        unless $self->has_title;
+};
    
+
        
+
+
    
+  
    Uses for before
    
+
+  
+
+  
    package Person;
+use Moose;
+
+before work => sub {
+    my $self = shift;
+    return unless $DEBUG;
+
+    warn "Called work on ",
+         $self->full_name,
+         "with the arguments: [@_]\n";
+};
    
+
        
+
+
    
+  
    Uses for after
    
+
+  
+
+  
    package Person;
+use Moose;
+
+after work => sub {
+    my $self = shift;
+    $self->work_count(
+        $self->work_count + 1 );
+};
    
+
    
+
+
    
+  
    Other Uses
    
+
+  
+
    
+
+
    
+  
    More Modifier Examples
    
+
+  
    has password => (
+     is      => 'rw',
+     clearer => 'clear_password',
+);
+has hashed_password => (
+     is      => 'ro',
+     builder => '_build_hashed_password',
+     clearer => '_clear_hashed_password',
+);
+after clear_password => sub {
+    my $self = shift;
+    $self->_clear_hashed_password;
+};
    
+
    
+
+
    
+  
    before and after Limitations
    
+
+  
+
    
+
+
    
+  
    The around Modifier
    
+
+  
+
    
+
+
    
+  
    The power of around
    
+
+  
    around insert => sub {
+    my $orig = shift;
+    my $self = shift;
+
+    $self->_validate_insert(@_);
+
+    my $new_user =
+        $self->$orig(
+            $self->_munge_insert(@_) );
+
+    $new_user->_assign_uri;
+    return $new_user;
+};
    
+
    
+
+
    
+  
    Modifier Order
    
+
+  
+
    
+
+
    
+  
    Modifier Order Illustrated
    
+
+
    +before 2
+ before 1
+  around 2
+   around 1
+    wrapped method
+   around 1
+  around 2
+ after 1
+after 2
+
    
+
    
+
+
    
+  
    Modifiers in Roles
    
+
+  
+
    
+
+
    
+  
    Modifiers in Roles
    
+
+  
    package IsUnreliable;
+use Moose::Role;
+
+requires 'run';
+
+around run => sub {
+    my $orig = shift;
+    my $self = shift;
+
+    return if rand(1) < 0.5;
+
+    return $self->$orig(@_);
+};
    
+
    
+
+
    
+  
    Augment and Inner
    
+
+  
+
    
+
+
    
+  
    Augment and Inner
    
+
+  
    package Document;
+
+sub xml { '<doc>' . inner() . '</doc>' }
+
+package Report;
+extends 'Document';
+augment xml =>
+    sub { title() . inner() . summary() };
+
+package TPSReport;
+extends 'Report';
+augment xml =>
+    sub { tps_xml() . inner() };
    
+
    
+
+
    
+  
    Augment and Inner
    
+
+  
+
    
+
+
    
+  
    Augment and Inner Usage
    
+
+  
+
    
+
+
    
+  
    Method Modifiers Summary
    
+
+  
+
    
+
+
    
+  
    Method Modifiers Summary
    
+
+  
+
    
+
+
    
+  
    Method Modifiers Summary
    
+
+  
+
    
+
+
    
+  
    Questions?
    
+
      
+
+
    
+  
    Exercises
    
+
+  
    # cd exercises
+# perl bin/prove -lv \
+      t/04-method-modifiers.t
+
+Iterate til this passes all its tests
    
+
    
+
+
    
+  
    Part 5: Types
    
+
    
+
+
    
+  
    A Type System for Perl
    
+
+  
+
    
+
+
    
+  
    Components of a Moose Type
    
+
+  
+
    
+
+
    
+  
    Built-in Type Hierarchy
    
+
+  
    +Any
+Item
+    Bool
+    Maybe[`a]
+    Undef
+    Defined
+        Value
+           Num
+             Int
+           Str
+             ClassName
+             RoleName
+
    
+
    
+
+
    
+  
    Built-in Type Hierarchy
    
+
+
    +(Item)
+    (Defined)
+        (Value)
+        Ref
+            ScalarRef
+            ArrayRef[`a]
+            HashRef[`a]
+            CodeRef
+            RegexpRef
+            GlobRef
+              FileHandle
+            Object
+
    
+
    
+
+
    
+  
    Bool
    
+
+  
    True
    
+  
    1
+924.1
+'true'
+{}
    
+
+  
    False
    
+  
    0
+0.0
+'0'
+undef
    
+
+  
+
    
+
+
    
+  
    Value (and subtypes)
    
+
+  
+
    
+
+
    
+  
    ClassName and RoleName
    
+
+  
+
    
+
+
    
+  
    Parameterizable Types
    
+
+  
+
    
+
+
    
+  
    Maybe[`a]
    
+
+  
+
    
+
+
    
+  
    Type Union
    
+
+  
+
    
+
+
    
+  
    Making Your Own Types
    
+
+  
    use Moose::Util::TypeConstraints;
+
+subtype 'PositiveInt',
+    as      'Int',
+    where   { $_ > 0 },
+    message
+        { "The value you provided ($_)"
+          . " was not a positive int." };
+
+has size => (
+    is  => 'ro',
+    isa => 'PositiveInt',
+);
    
+
    
+
+
    
+  
    Automatic Types
    
+
+  
+
    
+
+
    
+  
    Automatic Types
    
+
+  
    package Employee;
+use Moose;
+
+has manager => (
+    is  => 'rw',
+    isa => 'Employee',
+);
+
+has start_date => (
+    is  => 'ro',
+    isa => 'DateTime',
+);
    
+
    
+
+
    
+  
    Subtype Shortcuts - class_type
    
+
+  
    use Moose::Util::TypeConstraints;
+class_type 'DateTime';
+
+subtype 'DateTime',
+    as      'Object',
+    where   { $_->isa('DateTime') },
+    message { ... };
    
+
    
+
+
    
+  
    Subtype Shortcuts - role_type
    
+
+  
    use Moose::Util::TypeConstraints;
+role_type 'Printable';
+
+subtype 'Printable',
+    as      'Object',
+    where
+        { Moose::Util::does_role(
+              $_, 'Printable' ) },
+    message { ... };
    
+
    
+
+
    
+  
    Subtype Shortcuts - duck_type
    
+
+  
    use Moose::Util::TypeConstraints;
+duck_type Car => qw( run break_down );
+
+subtype 'Car',
+    as      'Object',
+    where   { all { $_->can($_) }
+              qw( run break_down ) },
+    message { ... };
    
+
    
+
+
    
+  
    Subtype Shortcuts - enum
    
+
+  
    use Moose::Util::TypeConstraints;
+enum Color => qw( red blue green ) );
+
+my %ok = map { $_ => 1 }
+             qw( red blue green );
+
+subtype 'Color'
+    as      'Str',
+    where   { $ok{$_} },
+    message { ... };
    
+
    
+
+
    
+  
    Anonymous Subtypes
    
+
+  
    package Person;
+
+my $posint =
+    subtype as 'Int', where { $_ > 0 };
+
+has size => (
+    is  => 'ro',
+    isa => $posint,
+);
    
+
+  
+
    
+
+
    
+  
    Coercions
    
+
+  
    use Moose::Util::TypeConstraints;
+
+subtype 'UCStr',
+    as    'Str',
+    where { ! /[a-z]/ };
    
+
    
+
+
    
+  
    Coercions
    
+
+  
    coerce 'UCStr',
+    from 'Str',
+    via  { uc };
+
+has shouty_name => (
+    is     => 'ro',
+    isa    => 'UCStr',
+    coerce => 1,
+);
    
+
    
+
+
    
+  
    Coercion Examples
    
+
+  
    subtype 'My::DateTime',
+    as class_type 'DateTime';
+
+coerce 'My::DateTime',
+    from 'HashRef',
+    via  { DateTime->new( %{$_} ) };
+
+coerce 'My::DateTime',
+    from 'Int',
+    via  { DateTime->from_epoch(
+               epoch => $_ ) };
    
+
+  
+
    
+
+
    
+  
    Coercion Examples
    
+
+  
    coerce 'ArrayRef[Int]',
+    from 'Int',
+    via  { [ $_ ] };
    
+
+  
+
    
+
+
    
+  
    Using Types with Attributes
    
+
+  
    package Person;
+
+has height => (
+    is  => 'rw',
+    isa => 'Num',
+);
+
+has favorite_numbers => (
+    is     => 'rw',
+    isa    => 'ArrayRef[Int]',
+    coerce => 1,
+);
    
+
    
+
+
    
+  
    More Droppings
    
+
+  
+
+  
    package Person;
+
+use Moose;
+use Moose::Util::TypeConstraints;
+
+subtype ...;
+
+no Moose;
+no Moose::Util::TypeConstraints;
    
+
    
+
+
    
+  
    Typed Methods (Low-tech)
    
+
+  
    package Person;
+use MooseX::Params::Validate qw( validated_list );
+
+sub work {
+    my $self = shift;
+    my ( $tasks, $can_rest ) =
+        validated_list(
+            \@_,
+            tasks    =>
+                { isa    => 'ArrayRef[Task]',
+                  coerce => 1 },
+            can_rest =>
+                { isa     => 'Bool',
+                  default => 0 },
+        );
+    ...
+}
    
+
    
+
+
    
+  
    Typed Methods (High-tech)
    
+
+  
    package Person;
+
+use MooseX::Method::Signatures;
+
+method work ( ArrayRef[Task] :$tasks,
+                        Bool :$can_rest = 0 ) {
+    my $self = shift;
+
+    ...
+}
    
+
    
+
+
    
+  
    Digression: The Type Registry
    
+
+  
+
    
+
+
    
+  
    Danger!
    
+
+  
+
    
+
+
    
+  
    Namespace Fix
    
+
+  
+
    
+
+
    
+  
    Namespace Fix
    
+
+  
    use Moose::Util::TypeConstraints;
+subtype 'MyApp::Type::DateTime',
+    as 'DateTime';
+
+coerce 'MyApp::Type::DateTime',
+    from 'HashRef',
+    via  { DateTime->new( %{$_} ) }
+
+has creation_date => (
+    is     => 'ro',
+    isa    => 'MyApp::Type::DateTime',
+    coerce => 1,
+);
    
+
    
+
+
    
+  
    Namespace Fix
    
+
+  
    subtype 'MyApp::Type::ArrayOfInt',
+    as 'ArrayRef[Int]';
+
+coerce 'MyApp::Type::ArrayOfInt',
+    from 'Int',
+    via  { [ $_ ] };
    
+
    
+
+
    
+  
    Namespace Fix Pros and Cons
    
+
+  
+
    
+
+
    
+  
    MooseX::Types
    
+
+  
    package MyApp::Types;
+
+use MooseX::Types
+    -declare => [ qw( ArrayOfInt ) ];
+use MooseX::Types::Moose
+    qw( ArrayRef Int );
+
+subtype ArrayOfInt,
+    as ArrayRef[Int];
+
+coerce ArrayOfInt
+    from Int,
+    via  { [ $_ ] };
    
+
    
+
+
    
+  
    MooseX::Types
    
+
+  
    package MyApp::Account;
+
+use MyApp::Types qw( ArrayOfInt );
+
+has transaction_history => (
+    is  => 'rw',
+    isa => ArrayOfInt,
+);
    
+
    
+
+
    
+  
    MooseX::Types
    
+
+  
+
    
+
+
    
+  
    MooseX::Types Pros and Cons
    
+
+  
+
    
+
+
    
+  
    Recommendation
    
+
+  
+
    
+
+
    
+  
    Questions?
    
+
      
+
+
    
+  
    Exercises
    
+
+  
    # cd exercises
+# perl bin/prove -lv t/05-types.t
+
+Iterate til this passes all its tests
    
+
    
+
+
    
+  
    Part 6: Advanced Attributes
    
+
    
+
+
    
+  
    Weak References
    
+
+  
+
    
+
+
    
+  
    Circular Reference Illustrated
    
+
+  
    my $foo = {};
+my $bar = { foo => $foo };
+$foo->{bar} = $bar;
    
+
+  
+
    
+
+
    
+  
    Weakening Circular References
    
+
+  
    use Scalar::Util qw( weaken );
+
+my $foo = {};
+my $bar = { foo => $foo };
+$foo->{bar} = $bar;
+weaken $foo->{bar}
    
+
+  
+
    
+
+
    
+  
    Circular References in Attributes
    
+
+  
    package Person;
+use Moose;
+
+has name   => ( is => 'ro' );
+has friend => ( is => 'rw' );
+
+my $alice = Person->new( name => 'Alice' );
+my $bob   = Person->new( name => 'Bob' );
+$bob->friend($alice);
+$alice->friend($bob);
    
+
    
+
+
    
+  
    The Fix
    
+
+  
    package Person;
+use Moose;
+
+has name   => ( is => 'ro' );
+has friend => ( is       => 'rw',
+                weak_ref => 1 );
+
+my $alice = Person->new( name => 'Alice' );
+my $bob   = Person->new( name => 'Bob' );
+$bob->friend($alice);
+$alice->friend($bob);
    
+
    
+
+
    
+  
    Under the Hood
    
+
+  
+
    
+
+
    
+  
    Triggers
    
+
+  
+
+  
    Gross
    
+
+  
    after salary_level => {
+    my $self = shift;
+    return unless @_;
+    $self->clear_salary;
+};
    
+
    
+
+
    
+  
    Use a Trigger Instead
    
+
+  
    Cleaner
    
+
+  
    has salary_level => (
+    is      => 'rw',
+    trigger => sub { $_[0]->clear_salary },
+);
    
+
    
+
+
    
+  
    Delegation
    
+
+  
+
    
+
+
    
+  
    Delegation Examples
    
+
+  
    package Person;
+
+has lungs => (
+    is      => 'ro',
+    isa     => 'Lungs',
+    handles => [ 'inhale', 'exhale' ],
+);
    
+
+  
+
    
+
+
    
+  
    Why Delegation?
    
+
+  
+
     
+
+
    
+  
    Moose's handles Parameter
    
+
+  
+
          
+
+
    
+  
    Array Reference
    
+
+  
+
    
+
+
    
+  
    Hash Reference
    
+
+  
+
+  
    package Person;
+use Moose;
+has account => (
+    is      => 'ro',
+    isa     => 'BankAccount',
+    handles => {
+        receive_money => 'deposit',
+        give_money    => 'withdraw',
+    },
+);
    
+
    
+
+
    
+  
    Hash Reference Detailed
    
+
+  
        handles => {
+        receive_money => 'deposit',
+        give_money    => 'withdraw',
+    },
    
+
+  
+
    
+
+
    
+  
    Regex
    
+
+  
    package Person;
+use Moose;
+
+has name => (
+    is      => 'ro',
+    isa     => 'Name',
+    handles => qr/.*/,
+);
    
+
+  
+
    
+
+
    
+  
    Role Name
    
+
+  
    package Auditor;
+use Moose::Role;
+sub record_change  { ... }
+sub change_history { ... }
+
+package Account;
+use Moose;
+
+has history => (
+    is      => 'ro',
+    does    => 'Auditor',
+    handles => 'Auditor',
+);
    
+
    
+
+
    
+  
    Role Name Detailed
    
+
+  
+
    
+
+
    
+  
    Native Delegation
    
+
+  
+
    
+
+
    
+  
    Native Delegation - Array(Ref)
    
+
+  
+
    
+
+
    
+  
    Native Delegation - Array(Ref)
    
+
+  
    package Person;
+use Moose;
+has _favorite_numbers => (
+    traits   => [ 'Array' ],
+    is       => 'ro',
+    isa      => 'ArrayRef[Int]',
+    default  => sub { [] },
+    init_arg => undef,
+    handles  =>
+      { favorite_numbers    => 'elements',
+        add_favorite_number => 'push',
+      },
+);
    
+
    
+
+
    
+  
    Native Delegation - Array(Ref)
    
+
+  
    my $person = Person->new();
+
+$person->add_favorite_number(7);
+$person->add_favorite_number(42);
+
+print "$_\n"
+    for $person->favorite_numbers;
+
+# 7
+# 42
    
+
    
+
+
    
+  
    Native Delegation
    
+
+  
+
    
+
+
    
+  
    Curried Delegation
    
+
+  
+
    
+
+
    
+  
    Curried Delegation
    
+
+  
    package Person;
+use Moose;
+has account => (
+    is      => 'ro',
+    isa     => 'BankAccount',
+    handles => {
+        receive_100 =>
+            [ 'deposit', 100 ]
+        give_100    =>
+            [ 'withdraw', 100 ]
+    },
+);
    
+
    
+
+
    
+  
    Traits and Metaclasses
    
+
+  
+
    
+
+
    
+  
    Traits and Metaclasses
    
+
+  
+
    
+
+
    
+  
    Traits and Metaclasses
    
+
+  
+
    
+
+
    
+  
    Simple Trait Example
    
+
+  
    package Person;
+use Moose;
+use MooseX::LabeledAttributes;
+
+has ssn => (
+    traits => [ 'Labeled' ],
+    is     => 'ro',
+    isa    => 'Str',
+    label  => 'Social Security Number',
+);
+print Person->meta
+            ->get_attribute('ssn')->label;
    
+
    
+
+
    
+  
    Simple Metaclass Example
    
+
+  
    package Person;
+use Moose;
+use MooseX::LabeledAttributes;
+
+has ssn => (
+    metaclass =>
+        'MooseX::Meta::Attribute::Labeled',
+    is        => 'ro',
+    isa       => 'Str',
+    label     => 'Social Security Number',
+);
+print Person->meta
+            ->get_attribute('ssn')->label;
    
+
    
+
+
    
+  
    Traits vs Metaclass
    
+
+  
+
    
+
+
    
+  
    Advanced Attributes Summary
    
+
+  
+
    
+
+
    
+  
    Questions?
    
+
      
+
+
    
+  
    Exercises
    
+
+  
    # cd exercises
+# perl bin/prove -lv \
+      t/06-advanced-attributes.t
+
+Iterate til this passes all its tests
    
+
    
+
+
    
+  
    Part 7: Introspection
    
+
    
+
+
    
+  
    Part 8: A Brief Tour of MooseX
    
+
    
+
+
    
+  
    Notable Moose Extensions on CPAN
    
+
+  
+
    
+
+
    
+  
    Already Mentioned Several
    
+
+  
+
        
+
+
    
+  
    MooseX::Declare
    
+
+
    use MooseX::Declare;
+use 5.10.0; # for say
+
+class Person {
+    has greeting
+        => ( is => 'ro', isa => 'Str' );
+
+    method speak {
+        say $self->greeting;
+    }
+}
    
+
    
+
+
    
+  
    MooseX::Declare
    
+
+  
+
    
+
+
    
+  
    MooseX::StrictConstructor
    
+
+  
+
    
+
+
    
+  
    MooseX::StrictConstructor
    
+
+  
    package Person;
+
+use Moose;
+use MooseX::StrictConstructor;
+
+has name => ( is => 'ro' );
+
+Person->new
+    ( nane => 'Ringo Shiina' ); # kaboom
    
+
    
+
+
    
+  
    MooseX::Traits
    
+
+  
+
    
+
+
    
+  
    MooseX::Traits
    
+
+  
    package MyApp::Thingy;
+use Moose;
+
+with 'MooseX::Traits';
+
+my $thing =
+    MyApp::Thingy->new_with_traits
+        ( traits => [ 'Foo', 'Bar' ],
+          size   => 42 );
    
+
    
+
+
    
+  
    MooseX::Getopt
    
+
+  
+
    
+
+
    
+  
    MooseX::Getopt
    
+
+  
    package App::CLI;
+use Moose;
+
+with 'MooseX::Getopt';
+
+has file    =>
+    ( is => 'ro', required => 1 );
+has filters =>
+    ( is => 'ro', isa => 'Str' );
+
+sub run { ... }
    
+
    
+
+
    
+  
    MooseX::Getopt
    
+
+  
+
+
    #!/usr/bin/perl
+
+use App::CLI;
+
+App::CLI->new_with_options()->run();
    
+
+
    $ myapp-cli \
+   --file foo \
+   --filters compress \
+   --filters sanitize
    
+
    
+
+
    
+  
    MooseX::Clone
    
+
+  
    package Person;
+
+use Moose;
+with 'MooseX::Clone';
+
+my $person = Person->new;
+my $clone  = $person->clone;
    
+
    
+
+
    
+  
    MooseX::NonMoose
    
+
+  
+
    
+
+
    
+  
    MooseX::Role::Parameterized
    
+
+  
    package HasCollection;
+use MooseX::Role::Parameterized;
+
+parameter type => ( isa     => 'Str',
+                    default => 'Item' );
+role {
+    my $p = shift;
+
+    my $type = 'ArrayRef[' . $p->type() . ']';
+    has collection =>
+        ( is  => 'ro',
+          isa => $type );
+};
    
+
    
+
+
    
+  
    MooseX::Role::Parameterized
    
+
+  
    package Person;
+
+use Moose;
+with HasCollection => { type => 'Int' };
    
+
    
+
+
    
+  
    Questions?
    
+
      
+
+
    
+  
    Part 9: Writing Moose Extensions
    
+
    
+
+
    
+  
    The End
    
+
    
+
+
    
+  
    More Information
    
+
+  
+
    
+
+ 
+
+
+
+