scope::guard(3pm) [debian man page]

Scope::Guard(3pm)					User Contributed Perl Documentation					 Scope::Guard(3pm)

NAME

       Scope::Guard - lexically-scoped resource management

SYNOPSIS

	   my $guard = guard { ... };

	     # or

	   my $guard = scope_guard &handler;

	     # or

	   my $guard = Scope::Guard->new(sub { ... });

	   $guard->dismiss(); # disable the handler

DESCRIPTION

       This module provides a convenient way to perform cleanup or other forms of resource management at the end of a scope. It is particularly
       useful when dealing with exceptions: the "Scope::Guard" constructor takes a reference to a subroutine that is guaranteed to be called even
       if the thread of execution is aborted prematurely. This effectively allows lexically-scoped "promises" to be made that are automatically
       honoured by perl's garbage collector.

       For more information, see: <http://www.drdobbs.com/cpp/184403758>

METHODS

   new
	   my $guard = Scope::Guard->new(sub { ... });

	     # or

	   my $guard = Scope::Guard->new(&handler);

       The "new" method creates a new "Scope::Guard" object which calls the supplied handler when its "DESTROY" method is called, typically at the
       end of the scope.

   dismiss
	   $guard->dismiss();

	     # or

	   $guard->dismiss(1);

       "dismiss" detaches the handler from the "Scope::Guard" object. This revokes the "promise" to call the handler when the object is destroyed.

       The handler can be re-enabled by calling:

	   $guard->dismiss(0);

EXPORTS

   guard
       "guard" takes a block and returns a new "Scope::Guard" object. It can be used as a shorthand for:

	   Scope::Guard->new(...)

       e.g.

	   my $guard = guard { ... };

       Note: calling "guard" anonymously, i.e. in void context, will raise an exception.  This is because anonymous guards are destroyed
       immediately (rather than at the end of the scope), which is unlikely to be the desired behaviour.

   scope_guard
       "scope_guard" is the same as "guard", but it takes a code ref rather than a block.  e.g.

	   my $guard = scope_guard &handler;

       or:

	   my $guard = scope_guard sub { ... };

       or:

	   my $guard = scope_guard $handler;

       As with "guard", calling "scope_guard" in void context will raise an exception.

VERSION

       0.20

SEE ALSO

       o   B::Hooks::EndOfScope

       o   End

       o   Guard

       o   Hook::Scope

       o   Object::Destroyer

       o   Perl::AtEndOfScope

       o   ReleaseAction

       o   Scope::local_OnExit

       o   Scope::OnExit

       o   Sub::ScopeFinalizer

       o   Value::Canary

AUTHOR

       chocolateboy <chocolate@cpan.org>

COPYRIGHT

       Copyright (c) 2005-2010, chocolateboy.

       This module is free software. It may be used, redistributed and/or modified under the same terms as Perl itself.

perl v5.10.1							    2010-05-16							 Scope::Guard(3pm)

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LWP::Protocol::PSGI(3pm)				User Contributed Perl Documentation				  LWP::Protocol::PSGI(3pm)

NAME

       LWP::Protocol::PSGI - Override LWP's HTTP/HTTPS backend with your own PSGI applciation

SYNOPSIS

	 use LWP::UserAgent;
	 use LWP::Protocol::PSGI;

	 # can be Mojolicious, Catalyst ... any PSGI application
	 my $psgi_app = do {
	     use Dancer;
	     setting apphandler => 'PSGI';
	     get '/search' => sub {
		 return 'googling ' . params->{q};
	     };
	     dance;
	 };

	 LWP::Protocol::PSGI->register($psgi_app);

	 # can hijack any code or module that uses LWP::UserAgent underneath, with no changes
	 my $ua  = LWP::UserAgent->new;
	 my $res = $ua->get("http://www.google.com/search?q=bar");
	 print $res->content; # "googling bar"

DESCRIPTION

       LWP::Protocol::PSGI is a module to hijack any code that uses LWP::UserAgent underneath such that any HTTP or HTTPS requests can be routed
       to your own PSGI application.

       Because it works with any code that uses LWP, you can override various WWW::*, Net::* or WebService::* modules such as WWW::Mechanize,
       without modifying the calling code or its internals.

	 use WWW::Mechanize;
	 use LWP::Protocol::PSGI;

	 LWP::Protocol::PSGI->register($my_psgi_app);

	 my $mech = WWW::Mechanize->new;
	 $mech->get("http://amazon.com/"); # $my_psgi_app runs

METHODS

       register
	     LWP::Protocol::PSGI->register($app);
	     my $guard = LWP::Protocol::PSGI->register($app);

	   Registers an override hook to hijack HTTP requests. If called in a non-void context, returns a Guard object that automatically resets
	   the override when it goes out of context.

	     {
		 my $guard = LWP::Protocol::PSGI->register($app);
		 # hijack the code using LWP with $app
	     }

	     # now LWP uses the original HTTP implementations

       unregister
	     LWP::Protocol::PSGI->unregister;

	   Resets all the overrides for LWP. If you use the guard interface described above, it will be automatically called for you.

AUTHOR

       Tatsuhiko Miyagawa <miyagawa@bulknews.net>

COPYRIGHT

       Copyright 2011- Tatsuhiko Miyagawa

LICENSE

       This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

       Plack::Client LWP::UserAgent

perl v5.12.3							    2011-05-12						  LWP::Protocol::PSGI(3pm)

Linux and UNIX Man Pages

scope::guard(3pm) [debian man page]

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