X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=moose-class%2Fslides%2Findex.html;h=22cef8e555d859c71e0ceec4a9b99d002de5d6d2;hb=b8e08963464459d4f6dd8ccb03f74bf17813273f;hp=e44c60eb157493cf221bf334fec77de3d1a5ed39;hpb=e326acd629d05406fd326f7d306f3bbb1871ccff;p=gitmo%2Fmoose-presentations.git
diff --git a/moose-class/slides/index.html b/moose-class/slides/index.html
index e44c60e..22cef8e 100644
--- a/moose-class/slides/index.html
+++ b/moose-class/slides/index.html
@@ -52,7 +52,17 @@ img#me05 {top: 43px;left: 36px;}
+
- Calls
Person->BUILDARGS(@_)
to turn @_
into a hashref
- Blesses a reference
- Populates attributes based on the hashref from #1
- - Calls
$new_object->BUILDALL($constructor_args)
+ - Calls
$new_object->BUILDALL($constructor_args)
... which calls all BUILD
methods
- Returns the object
@@ -956,6 +977,7 @@ sub BUILD {
- Like
DESTROY
, but Moose makes sure all DEMOLISH
methods in a hierarchy are called
- Called in normal inheritance order, children to parents
+ - Never called by you, only by Perl itself
@@ -964,6 +986,8 @@ sub BUILD {
extends
is sugar for declaring parent classes
+ - Also ensures metaclass compatibility between parent and child
+ - Do not
use base
package Employee;
@@ -1017,6 +1041,7 @@ extends 'LWP';
override
is another method modifier
- An alternative to Perl's
SUPER::
+ - Declares your intent to override a method
@@ -1044,6 +1069,7 @@ use Moose;
- Mostly like
$self->SUPER::work(@_)
- But cannot change
@_
!
- Binds the parent's method at compile time
+ - Parent determined by checking
Child->meta()->superclasses()
@@ -1084,8 +1110,7 @@ has first_name => ( is => 'ro' );
my $person =
Person->new( first_name => 'Dave' );
-$person->first_name('Stevan');
-print $person->first_name; # Dave
+$person->first_name('Stevan'); # dies
@@ -1104,7 +1129,7 @@ print $person->first_name; # Dave
use Moose;
# true
-Person->can('extends');
+Person->can('extends');
- Not very hygienic
@@ -1119,17 +1144,31 @@ use Moose;
...
-no Moose;
+no Moose;
+
+# false
+Person->can('extends');
+
+
+
+
Cleaning Up Moose Droppings
+
+
package Person;
+use namespace::autoclean;
+use Moose;
+
+...
# false
-Person->can('extends');
+Person->can('extends');
No Moose
- no Moose
at the end of a package is a best practice
+ - Cleaning up is a best practice
+ - Say
no Moose
at the end of a package
- Or
use namespace::autoclean
at the top
- Just do it
@@ -1139,13 +1178,13 @@ Person->can('extends');
Immutability
- - Stevan's Incantation of Fleet-Footedness
+ - Stevan's Incantation of Fleet-Footedness
package Person;
use Moose;
-__PACKAGE__->meta->make_immutable;
+
__PACKAGE__->meta->make_immutable;
@@ -1331,7 +1370,7 @@ sub print {
# or ...
-Person->meta->does('Printable')
+Person->meta->does_role('Printable')
@@ -1391,69 +1430,17 @@ use Moose;
-
Method Aliasing
-
-
package FragileDancer;
-use Moose;
-
-with 'IsFragile' =>
- { -alias =>
- { break => 'break_bone' } },
- 'CanBreakdance' =>
- { -alias =>
- { break => 'break_it_down' } };
-
-
- - Renames the roles' methods
- - Still conflicts, need to
exclude
as well
-
-
-
-
-
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
+
Conflicts Are a Smell
- - Roles are also about semantics!
- - We've fulfilled the letter and lost the spirit
+ - Roles are about semantics!
- Roles have a meaning
- - Think twice before blindly aliasing and excluding methods!
+ - Method name conflicts smell like bad design
-
Hot Role-on-Role Action
+
Roles With Roles
package Comparable;
use Moose::Role;
@@ -1462,7 +1449,7 @@ requires 'compare';
-
Hot Role-on-Role Action
+
Roles With Roles
package TestsEquality;
use Moose::Role;
@@ -1471,7 +1458,7 @@ with 'Comparable';
sub is_equal {
my $self = shift;
- return $self->compare(@_) == 0;
+ return $self->compare(@_) == 0;
}
@@ -1486,8 +1473,8 @@ with 'TestsEquality';
# Satisfies the Comparable role
sub compare { ... }
-Integer->does('TestsEquality'); # true
-Integer->does('Comparable'); # also true!
+Integer->does('TestsEquality'); # true
+Integer->does('Comparable'); # also true!
@@ -1509,11 +1496,11 @@ with 'HasSubProcess';
Delayed Conflict
-
package StateOfTexas;
+ package SysadminAssassin;
with 'Killer';
- StateOfTexas
must implement its own execute
+ SysadminAssassin
must implement its own execute
- But loading the
Killer
role by itself does not cause an error
@@ -1541,7 +1528,7 @@ use Moose;
with 'HasSize';
-has size => ( is => 'ro' );
+has size => ( is => 'ro' );
@@ -1555,7 +1542,7 @@ requires 'size';
package Shirt;
use Moose;
-has size => ( is => 'ro' );
+has size => ( is => 'ro' );
with 'HasSize';
@@ -1577,9 +1564,9 @@ with 'HasSize';
package Comparison;
use Moose;
-has [ 'left', 'right' ] => (
- is => 'ro',
- does => 'Comparable',
+has [ 'left', 'right' ] => (
+ is => 'ro',
+ does => 'Comparable',
);
@@ -1594,7 +1581,7 @@ has [ 'left', 'right' ] => (
use Moose::Util qw( apply_all_roles );
-my $fragile_person = Person->new( ... );
+my $fragile_person = Person->new( ... );
apply_all_roles( $fragile_person,
'IsFragile' );
@@ -1750,8 +1737,8 @@ has first_name => (
required => 1,
);
-Person->new( first_name => undef ); # ok
-Person->new(); # kaboom
+Person->new( first_name => undef ); # ok
+Person->new(); # kaboom
@@ -1759,7 +1746,7 @@ Person->new(); # kaboom
- Attributes can have defaults
- - Simple non-referecne scalars (number, string)
+ - Simple non-reference scalars (number, string)
- Subroutine reference
- A builder method
@@ -1844,7 +1831,8 @@ has packages => (
use Moose;
my $highlander_bank =
- Bank->new( name => 'Spire FCU' );
+ Bank->new(
+ name => 'Clan MacLeod Trust' );
has bank => (
is => 'rw',
@@ -1856,7 +1844,8 @@ has bank => (
Builder
- - A method name which returns the default
+ - A method name
+ - When called, this method returns the default value
@@ -1874,7 +1863,7 @@ has bank => (
sub _build_bank {
my $self = shift;
return Bank->new(
- name => 'Spire FCU' );
+ name => 'Spire FCU' );
}
@@ -1930,7 +1919,8 @@ has bank => (
use Moose;
has shoe_size => (
- is => 'ro',
+ is => 'ro',
+ required => 1,
);
@@ -1940,7 +1930,7 @@ has shoe_size => (
has shoes => (
is => 'ro',
lazy => 1,
- builder => '_build_shoes',
+ builder => '_build_shoes',
);
sub _build_shoes {
@@ -2013,16 +2003,16 @@ has account => (
package Person;
use Moose;
-has shoe_size => (
+has shoe_size => (
is => 'ro',
init_arg => 'foot_size',
);
-Person->new( shoe_size => 13 );
+Person->new( shoe_size => 13 );
my $person =
- Person->new( foot_size => 13 );
-print $person->shoe_size;
+ Person->new( foot_size => 13 );
+print $person->shoe_size;
@@ -2031,12 +2021,12 @@ print $person->shoe_size;
package Person;
use Moose;
-has shoes => (
+has shoes => (
is => 'ro',
init_arg => undef,
);
-Person->new( shoes => Shoes->new );
+Person->new(
shoes => Shoes->new );
@@ -2183,6 +2173,13 @@ has first_name => (
- Attributes can have a
default
or builder
- Attributes with a default or builder can be
lazy
- Attributes can have a
clearer
and/or predicate
+
+
+
+
+
Basic Attributes Summary
+
+
- An attribute's constructor name can be changed with
init_arg
- A subclass can alter its parents' attributes
- Attribute accessor names can be changed
@@ -2212,18 +2209,18 @@ Iterate til this passes all its tests
- Apply to an existing method
- - ... from a parent class, the current class, or a role
+ - ... that comes from a parent class, the current class, or a role
- Roles can provide modifiers that are applied at composition time
-
What is a Method Modifier
+
What Are Method Modifiers For?
- "Inject" behavior
- Add behavior to generated methods (accessors, delegations)
- - Provide roles which modify existing behavior
+ - Added from a role, can modify existing behavior
@@ -2350,7 +2347,7 @@ after clear_password => sub {
$self->$orig(
$self->_munge_insert(@_) );
- $new_user->_assign_uri;
+ $new_user->_assign_uri;
return $new_user;
};
@@ -2359,7 +2356,7 @@ after clear_password => sub {
Modifier Order
- - Before runs order from last to first
+ - Before runs in order from last to first
- After runs in order from first to last
- Around runs in order from last to first
@@ -2414,6 +2411,7 @@ around run => sub {
- Inverted
super
- From least- to most-specific
+ - Like Mason's autohandler feature
- Grandparent to parent to child
- Not allowed in roles
@@ -2422,19 +2420,21 @@ around run => sub {
Augment and Inner
-
package Document;
+ package Document;
sub xml { '<doc>' . inner() . '</doc>' }
package Report;
extends 'Document';
augment xml =>
- sub { title() . inner() . summary() };
+ sub { my $self = shift;
+ $self->title() . inner() . $self->summary() };
package TPSReport;
extends 'Report';
augment xml =>
- sub { tps_xml() . inner() };
+ sub { my $self = shift;
+ $self->tps_xml() . inner() };
@@ -2556,11 +2556,11 @@ Item
Undef
Defined
Value
- Num
- Int
- Str
- ClassName
- RoleName
+ Str
+ Num
+ Int
+ ClassName
+ RoleName
@@ -2570,6 +2570,7 @@ Item
(Item)
(Defined)
+ (Value)
Ref
ScalarRef
ArrayRef[`a]
@@ -2577,7 +2578,7 @@ Item
CodeRef
RegexpRef
GlobRef
- FileHandle
+ FileHandle
Object
@@ -2608,6 +2609,7 @@ undef
Value
is true when ! ref $thing
Value
and Str
are effectively the same, but Str
is more expressive
+ Num
is true when a $scalar
looks like a number
- An overloaded object which numifies does not pass the
Num
constraint!
- Perl 5's overloading is hopelessly broken
@@ -2708,9 +2710,11 @@ 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 { ... };
@@ -2720,10 +2724,12 @@ subtype 'DateTime',
Subtype Shortcuts - role_type
use Moose::Util::TypeConstraints;
-role_type 'Printable';
+role_type 'Printable';
-subtype 'Printable',
- as 'Object',
+
+
+subtype 'Printable',
+ as 'Object',
where
{ Moose::Util::does_role(
$_, 'Printable' ) },
@@ -2734,9 +2740,11 @@ subtype '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 ) },
@@ -2747,12 +2755,14 @@ subtype 'Car',
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'
+subtype 'Color'
as 'Str',
where { $ok{$_} },
message { ... };
@@ -2828,7 +2838,7 @@ coerce 'My::DateTime',
via { [ $_ ] };
- - Coerce instead of a union like
Int | ArrayRef[Int]
+ - Instead of union -
Int | ArrayRef[Int]
@@ -2853,7 +2863,7 @@ has favorite_numbers => (
More Droppings
- Moose::Util::TypeConstraint
also needs cleanup
+ Moose::Util::TypeConstraints
also needs cleanup
package Person;
@@ -2868,6 +2878,19 @@ no Moose;
+
Questions So Far?
+
+
+
+
Exercises
+
+
# cd exercises
+# perl bin/prove -lv t/05-types.t
+
+Iterate til this passes all its tests
+
+
+
Typed Methods (Low-tech)
package Person;
@@ -2880,7 +2903,7 @@ sub work {
\@_,
tasks =>
{ isa => 'ArrayRef[Task]',
- coerce =>1 },
+ coerce => 1 },
can_rest =>
{ isa => 'Bool',
default => 0 },
@@ -2908,7 +2931,7 @@ sub work {
Digression: The Type Registry
- - Types are actually
Moose::Meta::TypeConstraint
objects
+ - Types are actually
Moose::Meta::TypeConstraints
objects
- Stored in an interpreter-global registry mapping names to objects
@@ -2998,9 +3021,9 @@ coerce ArrayOfInt
use MyApp::Types qw( ArrayOfInt );
-has transaction_history => (
- is => 'rw',
- isa => ArrayOfInt,
+has transaction_history => (
+ is => 'rw',
+ isa => ArrayOfInt,
);
@@ -3010,7 +3033,7 @@ has transaction_history => (
- Type names are exported functions, catches typos early
- Types must be pre-declared
- - Types are stored with namespaces internally, but externally are short
+ - Types are stored with namespaces internally, but you use short names
- Import existing Moose types as functions from
MooseX::Types::Moose
- Still need string names for things like
ArrayRef['Email::Address']
@@ -3023,7 +3046,7 @@ has transaction_history => (
- Catches typos at compile time
- Automatic namespacing
- One more thing to install and learn
- - Every name gets types twice (declared and then defined)
+ - Every name is typed twice (declared and then defined)
- Still stuck with strings when referring to class or role names
- Coercion gotcha from earlier still applies to types exported from
MooseX::Types::Moose
@@ -3044,15 +3067,6 @@ has transaction_history => (
Questions?
-
-
Exercises
-
-
# cd exercises
-# perl bin/prove -lv t/05-types.t
-
-Iterate til this passes all its tests
-
-
Part 6: Advanced Attributes
@@ -3150,7 +3164,7 @@ $alice->friend($bob);
after salary_level => {
my $self = shift;
- return unless @_;
+ return unless @_;
$self->clear_salary;
};
@@ -3162,11 +3176,22 @@ $alice->friend($bob);
has salary_level => (
is => 'rw',
- trigger => sub { $_[0]->clear_salary },
+ trigger =>
+ sub { $_[0]->clear_salary },
);
+
Trigger Arguments
+
+
+ $self
+ $new_value
+ $old_value
- if one exists
+
+
+
+
Delegation
@@ -3182,7 +3207,7 @@ $alice->friend($bob);
has lungs => (
is => 'ro',
- isa => 'Lungs',
+ isa => 'Lungs',
handles => [ 'inhale', 'exhale' ],
);
@@ -3223,6 +3248,7 @@ has lungs => (
Array Reference
+ - 1-to-1 mapping
- Takes each method name and creates a simple delegation from the delegating class to the delegatee attribute
@@ -3315,17 +3341,37 @@ has history => (
- Delegate to unblessed Perl types
- Scalar, array or hash ref, etc
+ - Treat Perl types as objects
+ - Still uses
handles
+ - Pretend that native Perl types have methods
+
+
+
+
+
Native Delegation - Array(Ref)
+
+
+ - Methods include:
+
+ push
+ shift
+ elements
- returns all elements
+ count
+ is_empty
+ - quite a few more
+
+
-
Native Delegation - Array
+
Native Delegation - Array(Ref)
package Person;
use Moose;
has _favorite_numbers => (
traits => [ 'Array' ],
- is => 'ro',
+ is => 'bare',
isa => 'ArrayRef[Int]',
default => sub { [] },
init_arg => undef,
@@ -3337,23 +3383,71 @@ has _favorite_numbers => (
-
Native Delegation - Counter
+
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
+
+
+ - Native types are ...
+
+ - Number -
add
, mul
, ...
+ - String -
append
, chop
, ...
+ - Counter -
inc
, dec
, ...
+ - Bool -
set
, toggle
, ...
+ - Hash -
get
, set
, ...
+ - Array - already saw it
+ - Code -
execute
and execute_method
+
+
+
+
+
+
+
Curried Delegation
+
+
+ - A delegation with some preset arguments
+ - Works with object or Native delegation
+
+
+
+
+
Curried Delegation
-
package Stack;
+ package Person;
use Moose;
-has depth => (
- traits => [ 'Counter' ],
- is => 'ro',
- isa => 'Int',
- default => 0,
- init_arg => undef,
- handles =>
- { _inc_depth => 'inc',
- _dec_depth => 'dec',
- },
+has account => (
+ is => 'ro',
+ isa => 'BankAccount',
+ handles => {
+ receive_100 =>
+ [ 'deposit', 100 ]
+ give_100 =>
+ [ 'withdraw', 100 ]
+ },
);
+
+
Curried Delegation
+
+
$person->receive_100;
+# really is
+$person->account->deposit(100);
+
Traits and Metaclasses
@@ -3380,7 +3474,7 @@ has depth => (
Traits and Metaclasses
- - Can add/alter/remove attribute parameter (from
has
)
+ - Can add/alter/remove an attribute parameter (from
has
)
- Can change behavior of created attribute
@@ -3438,15 +3532,12 @@ print Person->meta
- Use
weak_ref
to avoid circular references
- 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
@@ -3456,20 +3547,228 @@ print Person->meta
Iterate til this passes all its tests
-
-
Part 7: Introspection
+
+
CYOA
+
+
+ If there is time, keep going ...
+
+
+
+ Otherwise, jump to slide 269 ...
+
-
Part 8: A Tour of MooseX
+ Bonus: A Brief Tour of MooseX
-
-
Part 9: Writing Moose Extensions
+
+
Notable MX Modules on CPAN
+
+
+ - Not comprehensive
+ - 152 MooseX distributions on CPAN as of 02/02/2010
+ - Some of them are crap
+
-
-
The End
+
+
Already Mentioned Several
+
+
+ MooseX::NonMoose
- best solution for subclassing non-Moose parents
+ MooseX::Declare
- real Perl 5 OO
+ MooseX::FollowPBP
and MooseX::SemiAffordanceAccessor
+ MooseX::Params::Validate
and MooseX::Method::Signatures
+ MooseX::Types
+
+
+
+
+
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
+
+
+ - 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?)
+
+
+
+
+
MooseX::StrictConstructor
+
+
+ - By default, unknown constructor arguments are ignored
+ - MX::StrictConstructor turns these into an error
+
+
+
+
+
MooseX::StrictConstructor
+
+
package Person;
+
+use Moose;
+use MooseX::StrictConstructor;
+
+has name => ( is => 'ro' );
+
+Person->new
+ ( nane => 'Ringo Shiina' ); # kaboom
+
+
+
+
MooseX::Traits
+
+
+ - Combines object construction and role application
+ - Makes it easy to create one-off customized objects
+
+
+
+
+
MooseX::Traits
+
+
package MyApp::Thingy;
+use Moose;
+
+with 'MooseX::Traits';
+
+my $thing =
+ MyApp::Thingy->new_with_traits
+ ( traits => [ 'Foo', 'Bar' ],
+ size => 42 );
+
+
+
+
MooseX::Getopt
+
+
+ - Makes command-line interface programs easy!
+ - Construct an object from CLI arguments
+
+
+
+
+
MooseX::Getopt
+
+
package App::CLI;
+use Moose;
+
+with 'MooseX::Getopt';
+
+has file =>
+ ( is => 'ro', required => 1 );
+has filters =>
+ ( is => 'ro', isa => 'ArrayRef[Str]' );
+
+sub run { ... }
+
+
+
+
MooseX::Getopt
+
+
+ - Then call it like this:
+
+
+
#!/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
+
+
+ - Highly recommended for subclassing non-Moose parents
+ - Gets all the little annoying details right
+
+
+
+
+
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?
+
+
+
+
Moose-using Modules
+
+
+ For further reading, a few modules which use Moose ...
+
+
+
@@ -3482,10 +3781,14 @@ Iterate til this passes all its tests
- mailing list - moose@perl.org
- Slides and exercises are in Moose's git repo:
- git://jules.scsys.co.uk/gitmo/moose-presentations
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git://jules.scsys.co.uk/gitmo/moose-presentations
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The End
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