X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=moose-class%2Fslides%2Findex.html;h=e8302e4e73cbe636f765ed888232e74e28c1cd6d;hb=a88cc08084397dc7667e26dc315fb5492d8bf558;hp=e255a3ea3d116d28d5463e0364b31851938e5a11;hpb=aba801c43616ba77148f72748c53499cc35d8257;p=gitmo%2Fmoose-presentations.git diff --git a/moose-class/slides/index.html b/moose-class/slides/index.html index e255a3e..e8302e4 100644 --- a/moose-class/slides/index.html +++ b/moose-class/slides/index.html @@ -52,7 +52,7 @@ img#me05 {top: 43px;left: 36px;}

Introduction to Moose

-

Dave Rolsky +

Dave Rolsky

@@ -71,8 +71,8 @@ img#me05 {top: 43px;left: 36px;}
@@ -155,7 +155,7 @@ img#me05 {top: 43px;left: 36px;} 
package Person;
 use Moose;
 
-has first_name => ( is => 'rw' );
+has first_name => ( is => 'ro' ); @@ -950,10 +950,10 @@ sub BUILD {

Object Construction a la Moose

- 
Person->new(@_)
+ 
Person->new(@args)
    -
  1. Calls Person->BUILDARGS(@_) to turn @_ into a hashref
    2. +
  2. Calls Person->BUILDARGS(@args) to turn @args into a hashref
  3. Blesses a reference
  4. Populates attributes based on the hashref from #1
  5. Calls $new_object->BUILDALL($constructor_args) @@ -1032,7 +1032,7 @@ extends 'LWP';
  6. No DEMOLISH()
    7. -
  7. But see MooseX::NonMoose for a workaround
    8. +
  8. But MooseX::NonMoose fixes all of this
@@ -1054,13 +1054,13 @@ use Moose; extends 'Person'; -override work => sub { +override work => sub { my $self = shift; die "Pay me first" unless $self->got_paid; - super(); -}; + super(); +};
@@ -1069,7 +1069,7 @@ use Moose;
@@ -1155,8 +1155,8 @@ Person->can('extends');

Cleaning Up Moose Droppings

package Person;
-use namespace::autoclean;
 use Moose;
+use namespace::autoclean;
 
 ...
 
@@ -1234,7 +1234,7 @@ use Moose;
 
 # perl bin/prove -lv t/00-prereq.t
 
-# perl install-moose (if needed)
+## Read the instructions in t/01-classes.t
 
 # perl bin/prove -lv t/01-classes.t
 
@@ -1307,30 +1307,32 @@ sub print {
   
package Person;
 use Moose;
 
-with 'HasPermissions';

+with 'Printable';

Classes Consume Roles

-
my $person = Person->new(
+
package Person;
+
+sub as_string { $_[0]->first_name() }
+
+...
+
+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';

+$person->print();

Roles in Practice

@@ -1340,7 +1342,9 @@ print $person->full_name 
package Person;
 use Moose;
 
-with 'Printable';
+with 'Printable'; + +sub as_string { $_[0]->first_name() }
@@ -1351,6 +1355,8 @@ use Moose; with 'Printable'; +sub as_string { $_[0]->first_name() } + has has_been_printed => ( is => 'rw' ); sub print { @@ -1479,34 +1485,6 @@ 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 SysadminAssassin;
-with 'Killer';
- - -
- -

Roles as Interfaces

@@ -1656,8 +1634,6 @@ requires 'compare';

Real Examples

- - -
-

Method Modifiers Summary

- -
@@ -2685,11 +2600,15 @@ has start_date => (

Subtype Shortcuts - class_type

use Moose::Util::TypeConstraints;
-class_type 'DateTime';
+ +class_type 'DateTime'; + +
-
subtype     'DateTime',
+

+subtype     'DateTime',
     as      'Object',
     where   { $_->isa('DateTime') },
     message { ... };

@@ -2699,11 +2618,15 @@ class_type 'DateTime';

Subtype Shortcuts - role_type

use Moose::Util::TypeConstraints;
-role_type 'Printable';
+ +role_type 'Printable'; + +
-
subtype 'Printable',
+

+subtype 'Printable',
     as  'Object',
     where
         { Moose::Util::does_role(
@@ -2715,11 +2638,15 @@ role_type 'Printable';

   
Subtype Shortcuts - duck_type

 
   
use Moose::Util::TypeConstraints;
-duck_type Car => qw( run break_down );

+
+duck_type Car => qw( run break_down );
+
+
-
subtype 'Car',
+

+subtype 'Car',
     as      'Object',
     where   { all { $_->can($_) }
               qw( run break_down ) },
@@ -2730,11 +2657,15 @@ duck_type Car => qw( run break_down );

   
Subtype Shortcuts - enum

 
   
use Moose::Util::TypeConstraints;
-enum Color => qw( red blue green );

+
+enum Color => qw( red blue green );
+
+
-
my %ok = map { $_ => 1 }
+

+my %ok = map { $_ => 1 }
              qw( red blue green );
 
 subtype     'Color'
@@ -2749,7 +2680,9 @@ subtype     'Color'
   
package Person;
 
 my $posint =
-    subtype as 'Int', where { $_ > 0 };
+    subtype
+        as 'Int',
+        where { $_ > 0 };
 
 has size => (
     is  => 'ro',
@@ -2808,7 +2741,8 @@ coerce 'My::DateTime',
 

   
Coercion Examples

 
-  
coerce 'ArrayRef[Int]',
+  
# BAD CODE - DO NOT COPY
+coerce 'ArrayRef[Int]',
     from 'Int',
     via  { [ $_ ] };

 
@@ -2906,7 +2840,7 @@ sub work {
   
Digression: The Type Registry

 
   
    
-    
  • Types are actually Moose::Meta::TypeConstraints objects
    • 
+    
  • Types are actually Moose::Meta::TypeConstraint objects
    • 
     
  • Stored in an interpreter-global registry mapping names to objects
    • 
   

 

@@ -3028,10 +2962,21 @@ has transaction_history => (
 
 
 

+  
Specio

+
+  
    
+    
  • My attempt to replace MooseX::Types and built-in types
    • 
+    
  • Third-system effect?
    • 
+    
  • Still alpha - needs some work
    • 
+  

+

+
+

   
Recommendation

 
   
    
-    
  • Use MooseX::Types
    • 
+    
  • Use MooseX::Types for now
    • 
+    
  • Switch to Specio when it's ready?
    • 
     
  • Compile time error catching and automatic namespacing are huge wins
    • 
     
  • Docs from Moose::Util::TypeConstraints are 98% compatible with MooseX::Types anyway
    • 
     
  • A function exported by a type library works wherever a type name would
    • 
@@ -3193,6 +3138,25 @@ has lungs => (
 

 
 

+  
Delegation Explained

+
+
package Person;
+
+has lungs => (
+    is      => 'ro',
+    isa     => 'Lungs',
+    handles => [ 'inhale', 'exhale' ],
+);
+
+sub inhale {
+    my $self = shift;
+    $self->lungs()->inhale();
+}
+
+sub exhale { ... }

+

+
+

   
Why Delegation?

 
   
    
@@ -3256,8 +3220,12 @@ has account => (
     },

 
   
    
-    
  • $person->receive_money = $person->account->deposit
    • 
-    
  • $person->give_money = $person->account->withdraw
    • 
+    
  • $person->receive_money
+      
    
+          = $person->account->deposit
    • 
+    
  • $person->give_money
+      
    
+          = $person->account->withdraw
    • 
   

 
 
@@ -3345,8 +3313,7 @@ has history => (
   
package Person;
 use Moose;
 has _favorite_numbers => (
-    traits   => [ 'Array' ],
-    is       => 'bare',
+    traits   => [ 'Array' ],
     isa      => 'ArrayRef[Int]',
     default  => sub { [] },
     init_arg => undef,
@@ -3409,7 +3376,7 @@ has account => (
     isa     => 'BankAccount',
     handles => {
         receive_100 =>
-            [ 'deposit', 100 ]
+            [ 'deposit', 100 ],
         give_100    =>
             [ 'withdraw', 100 ]
     },
@@ -3425,82 +3392,6 @@ $person->account->deposit(100);

 
 
 

-  
Traits and Metaclasses

-
-  
    
-    
  • The ultimate in customization
    • 
-    
  • Per attribute metaclasses
    • 
-    
  • Per attribute roles applied to the attribute metaclass
    • 
-    
  • Change the meta-level behavior
    • 
-  

-

-
-

-  
Traits and Metaclasses

-
-  
    
-    
  • The default metaclass is Moose::Meta::Attribute
    • 
-    
  • Controls accessor generation, defaults, delegation, etc.
    • 
-    
  • Adding a role to this metaclass (or replacing it) allows for infinite customization
    • 
-  

-

-
-

-  
Traits and Metaclasses

-
-  
    
-    
  • Can add/alter/remove an attribute parameter (from has)
    • 
-    
  • Can change behavior of created attribute
    • 
-  

-

-
-

-  
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

-
-  
    
-    
  • Can apply any mix of traits to an attribute
    • 
-    
  • But just one metaclass
    • 
-    
  • Traits (aka roles) can cooperate
    • 
-    
  • Metaclasses require you to pick just one
    • 
-  

-

-
-

   
Advanced Attributes Summary

 
   
    
@@ -3508,11 +3399,14 @@ print Person->meta
     
  • Use trigger to do an action post-attribute write
    • 
     
  • Use delegations to hide "internal" objects
    • 
     
  • Use native delegations to treat Perl types as objects
    • 
-    
  • Traits and metaclasses let you extend Moose's core attribute features
    • 
   

 

 
 

+  
Questions?

+
  
+
+

   
Exercises

 
   
# cd exercises
@@ -3543,7 +3437,7 @@ Iterate til this passes all its tests

 
   
    
     
  • Not comprehensive
    • 
-    
  • 177 MooseX distributions on CPAN as of 09/21/2010
    • 
+    
  • 188 MooseX distributions on CPAN as of 02/03/2011
    • 
     
  • Some of them are crap
    • 
   

 

@@ -3564,7 +3458,7 @@ Iterate til this passes all its tests

   
MooseX::Declare

 
 
use MooseX::Declare;
-use 5.10.0; # for say
+use 5.12.0; # for say
 
 class Person {
     has greeting =>
@@ -3583,7 +3477,7 @@ class Person {
     
  • Still experimental-ish, but seeing more and more use
    • 
     
  • Not a source filter!
    • 
     
  • Hooks into the Perl parser rather than filtering all your code
    • 
-    
  • But not supported by PPI, perltidy, etc.
    •  (yet?)
+    
  • But not supported by PPI, perltidy, etc. (yet?)
    • 
   
 
 
@@ -3737,12 +3631,13 @@ with HasCollection => { type => 'Int' };
    
   
    
 
   
 
 
@@ -3751,12 +3646,12 @@ with HasCollection => { type => 'Int' };
    @@ -3770,7 +3665,7 @@ with HasCollection => { type => 'Int' };