Beefy Boxes and Bandwidth Generously Provided by pair Networks
Don't ask to ask, just ask
 
PerlMonks  

Re^2: Tieing and Blessing

by anaconda_wly (Scribe)
on Jan 07, 2013 at 09:24 UTC ( #1011987=note: print w/ replies, xml ) Need Help??


in reply to Re: Tieing and Blessing
in thread Tieing and Blessing

I have the question is that firstly I didn't use DBM file yet and can't understand tie from its manual since lack the experience of dbm file. I think blessing is tieing a reference to a package actually.


Comment on Re^2: Tieing and Blessing
Re^3: Tieing and Blessing
by anazawa (Scribe) on Jan 26, 2013 at 15:27 UTC
    Though I don't understand how tie() works, too, I know how to use it ;) The following class represents a hash whose keys are case-insensitive:
    package Insensitive::Hash; use strict; use warnings; sub new { my ( $class, @args ) = @_; my %self; while ( my ($key, $value) = splice @args, 0, 2 ) { $self{ lc $key } = $value; } bless \%self, $class; } sub get { my ( $self, $key ) = @_; $self->{ lc $key }; } sub set { my ( $self, $key, $value ) = @_; $self->{ lc $key } = $value; } 1;
    How can we use Insensitive::Hash?
    use strict; use warnings; use Insensitive::Hash; my $hash = Insensitive::Hash->new( 'Content-Type' => 'text/plain', ); # $key is case-insensitive $hash->get( 'Content-Type' ); # => "text/plain" $hash->get( 'content-type' ); # => "text/plain" $hash->set( 'CONTENT-TYPE' => 'text/html' );
    To implement tie() interface, rename the method names of Insensitive::Hash as follows:
    package Insensitive::Hash; use strict; use warnings; # new -> TIEHASH # get -> FETCH # set -> STORE sub TIEHASH { my ( $class, @args ) = @_; my %self; while ( my ($key, $value) = splice @args, 0, 2 ) { $self{ lc $key } = $value; } bless \%self, $class; } sub FETCH { my ( $self, $key ) = @_; $self->{ lc $key }; } sub STORE { my ( $self, $key, $value ) = @_; $self->{ lc $key } = $value; } 1;
    How tie() works?
    use strict; use warnings; use Insensitive::Hash; tie my %hash, 'Insensitive::Hash', ( 'Content-Type' => 'text/plain' ); # <=> my $hash = Insensitive::Hash->TIEHASH( ... ) $hash{'Content-Type'}; # <=> $hash->FETCH( 'Content-Type' ); $hash{'content-type'}; # <=> $hash->FETCH( 'content-type' ); $hash{'CONTENT-TYPE'} = 'text/html'; # <=> $hash->STORE( 'CONTENT-TYPE' => 'text/html' );
    Insensitive::Hash was taken from "Object-oriented Perl" written by D. Conway. See also HTTP::Headers (field names are case-insensitive).

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1011987]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others making s'mores by the fire in the courtyard of the Monastery: (5)
As of 2014-11-28 04:41 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    My preferred Perl binaries come from:














    Results (193 votes), past polls