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MakeMethods::Evaled::HUser3Contributed Perl DocumeMakeMethods::Evaled::Hash(3)

NAME
       Class::MakeMethods::Evaled::Hash	- Typical hash methods

SYNOPSIS
	 package MyObject;
	 use Class::MakeMethods::Evaled::Hash (
	   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 Evaled::Hash	subclass of MakeMethods	provides a simple constructor
       and accessors for blessed-hash 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::Standard 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::Standard	for more
       syntax information.

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 hash and blesses it	into
	   that	class.

       o   If called on	a hash-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 key-value pairs,	appends	them to	the new	hash.
	   These arguments override any	copied values, and later arguments
	   with	the same name will override earlier ones.

       o   Returns the new instance.

       Sample declaration and usage:

	 package MyObject;
	 use Class::MakeMethods::Evaled::Hash (
	   new => 'new',
	 );
	 ...

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

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

	 # Copy	with overriding	value
	 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 a hash-based instance.

       o   Uses	the method name	as a hash key to access	the related value for
	   each	instance.

       o   If called without any arguments returns the current value.

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

       Sample declaration and usage:

	 package MyObject;
	 use Class::MakeMethods::Evaled::Hash (
	   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 a hash-based instance.

       o   Uses	the method name	as a hash key to access	the related value for
	   each	instance.

       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).

       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::Evaled::Hash (
	   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);

	 # 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 a hash-based instance.

       o   Uses	the method name	as a hash key to access	the related value for
	   each	instance.

       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).

       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::Evaled::Hash (
	   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');

	 # 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::Evaled for more about this family of
       subclasses.

perl v5.24.1			  2004-09-06	  MakeMethods::Evaled::Hash(3)

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

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