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MakeMethods::Basic::ArUser3Contributed Perl DocumeMakeMethods::Basic::Array(3)

NAME
       Class::MakeMethods::Basic::Array	- Basic	array methods

SYNOPSIS
	 package MyObject;
	 use Class::MakeMethods::Basic::Array (
	   new => 'new',
	   scalar => [ 'foo', 'bar' ],
	   array => 'my_list',
	   hash	=> 'my_index',
	 );
	 ...

	 # Constructor
	 my $obj = MyObject->new( foo => 'Foozle' );

	 # Scalar Accessor
	 print $obj->foo();

	 $obj->bar('Barbados');
	 print $obj->bar();

	 # Array accessor
	 $obj->my_list(0 => 'Foozle', 1	=> 'Bang!');
	 print $obj->my_list(1);

	 # Hash	accessor
	 $obj->my_index('broccoli' => 'Blah!', 'foo' =>	'Fiddle');
	 print $obj->my_index('foo');

DESCRIPTION
       The Basic::Array	subclass of MakeMethods	provides a basic constructor
       and accessors for blessed-array object instances.

   Calling Conventions
       When you	"use" this package, the	method names you provide as arguments
       cause subroutines to be generated and installed in your module.

       See "Calling Conventions" in Class::MakeMethods::Basic for a summary,
       or "USAGE" in Class::MakeMethods	for full details.

   Declaration Syntax
       To declare methods, pass	in pairs of a method-type name followed	by one
       or more method names. Valid method-type names for this package are
       listed in "METHOD GENERATOR TYPES".

       See "Declaration	Syntax"	in Class::MakeMethods::Basic for more syntax
       information.

   About Positional Accessors
       Each accessor method claims the next available spot in the array	to
       store its value in.

       The mapping between method names	and array positions is stored in a
       hash named %FIELDS in the target	package. When the first	positional
       accessor	is defined for a package, its %FIELDS are initialized by
       searching its inheritance tree.

       Caution:	Subclassing packages that use positional accessors is somewhat
       fragile,	since you may end up with two distinct methods assigned	to the
       same position. Specific cases to	avoid are:

       o   If you inherit from more than one class with	positional accessors,
	   the positions used by the two sets of methods will overlap.

       o   If your superclass adds additional positional accessors after you
	   declare your	first, they will overlap yours.

METHOD GENERATOR TYPES
   new - Constructor
       For each	method name passed, returns a subroutine with the following
       characteristics:

       o   If called as	a class	method,	makes a	new array and blesses it into
	   that	class.

       o   If called on	an array-based instance, makes a copy of it and
	   blesses the copy into the same class	as the original	instance.

       o   If passed a list of method-value pairs, calls each named method
	   with	the associated value as	an argument.

       o   Returns the new instance.

       Sample declaration and usage:

	 package MyObject;
	 use Class::MakeMethods::Basic::Array (
	   new => 'new',
	 );
	 ...

	 # Bare	constructor
	 my $empty = MyObject->new();

	 # Constructor with initial sequence of	method calls
	 my $obj = MyObject->new( foo => 'Foozle', bar => 'Barbados' );

	 # Copy	with overriding	sequence of method calls
	 my $copy = $obj->new( bar => 'Bob' );

   scalar - Instance Accessor
       For each	method name passed, uses a closure to generate a subroutine
       with the	following characteristics:

       o   Must	be called on an	array-based instance.

       o   Determines the array	position associated with the method name, and
	   uses	that as	an index into each instance to access the related
	   value.

       o   If called without any arguments returns the current value (or
	   undef).

       o   If called with an argument, stores that as the value, and returns
	   it,

       Sample declaration and usage:

	 package MyObject;
	 use Class::MakeMethods::Basic::Array (
	   scalar => 'foo',
	 );
	 ...

	 # Store value
	 $obj->foo('Foozle');

	 # Retrieve value
	 print $obj->foo;

   array - Instance Ref	Accessor
       For each	method name passed, uses a closure to generate a subroutine
       with the	following characteristics:

       o   Must	be called on an	array-based instance.

       o   Determines the array	position associated with the method name, and
	   uses	that as	an index into each instance to access the related
	   value.

       o   The value for each instance will be a reference to an array (or
	   undef).

       o   If called without any arguments, returns the	current	array-ref
	   value (or undef).

       o   If called with one argument,	uses that argument as an index to
	   retrieve from the referenced	array, and returns that	value (or
	   undef). If the single argument is an	array ref, then	a slice	of the
	   referenced array is returned.

       o   If called with a list of index-value	pairs, stores the value	at the
	   given index in the referenced array.	If the instance's value	was
	   previously undefined, a new array is	autovivified. The current
	   value in each position will be overwritten, and later arguments
	   with	the same index will override earlier ones. Returns the current
	   array-ref value.

       Sample declaration and usage:

	 package MyObject;
	 use Class::MakeMethods::Basic::Array (
	   array => 'bar',
	 );
	 ...

	 # Set values by position
	 $obj->bar(0 =>	'Foozle', 1 => 'Bang!');

	 # Positions may be overwritten, and in	any order
	 $obj->bar(2 =>	'And Mash', 1 => 'Blah!');

	 # Retrieve value by position
	 print $obj->bar(1);

	 # Retrieve slice of values by position
	 print join(', ', $obj->bar( [0, 2] ) );

	 # Direct access to referenced array
	 print scalar @{ $obj->bar() };

	 # Reset the array contents to empty
	 @{ $obj->bar()	} = ();

   hash	- Instance Ref Accessor
       For each	method name passed, uses a closure to generate a subroutine
       with the	following characteristics:

       o   Must	be called on an	array-based instance.

       o   Determines the array	position associated with the method name, and
	   uses	that as	an index into each instance to access the related
	   value.

       o   The value for each instance will be a reference to a	hash (or
	   undef).

       o   If called without any arguments, returns the	current	hash-ref value
	   (or undef).

       o   If called with one argument,	uses that argument as an index to
	   retrieve from the referenced	hash, and returns that value (or
	   undef). If the single argument is an	array ref, then	a slice	of the
	   referenced hash is returned.

       o   If called with a list of key-value pairs, stores the	value under
	   the given key in the	referenced hash. If the	instance's value was
	   previously undefined, a new hash is autovivified. The current value
	   under each key will be overwritten, and later arguments with	the
	   same	key will override earlier ones.	Returns	the current hash-ref
	   value.

       Sample declaration and usage:

	 package MyObject;
	 use Class::MakeMethods::Basic::Array (
	   hash	=> 'baz',
	 );
	 ...

	 # Set values by key
	 $obj->baz('foo' => 'Foozle', 'bar' => 'Bang!');

	 # Values may be overwritten, and in any order
	 $obj->baz('broccoli' => 'Blah!', 'foo'	=> 'Fiddle');

	 # Retrieve value by key
	 print $obj->baz('foo');

	 # Retrieve slice of values by position
	 print join(', ', $obj->baz( ['foo', 'bar'] ) );

	 # Direct access to referenced hash
	 print keys %{ $obj->baz() };

	 # Reset the hash contents to empty
	 @{ $obj->baz()	} = ();

SEE ALSO
       See Class::MakeMethods for general information about this distribution.

       See Class::MakeMethods::Basic for more about this family	of subclasses.

perl v5.24.1			  2004-09-06	  MakeMethods::Basic::Array(3)

NAME | SYNOPSIS | DESCRIPTION | METHOD GENERATOR TYPES | SEE ALSO

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