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curry(3)	      User Contributed Perl Documentation	      curry(3)

NAME
       curry - Create automatic	curried	method call closures for any class or
       object

SYNOPSIS
	 use curry;

	 my $code = $obj->curry::frobnicate('foo');

       is equivalent to:

	 my $code = sub	{ $obj->frobnicate(foo => @_) };

       Additionally,

	 use curry::weak;

	 my $code = $obj->curry::weak::frobnicate('foo');

       is equivalent to:

	 my $code = do {
	   Scalar::Util::weaken(my $weak_obj = $obj);
	   sub {
	     return unless $weak_obj; #	in case	it already went	away
	     $weak_obj->frobnicate(foo => @_)
	   };
	 };

       If you want to pass a weakened copy of an object	to a coderef, use the
       $weak  package variable:

	use curry::weak;

	my $code = $self->$curry::weak(sub {
	 my ($self, @args) = @_;
	 print "$self must still be alive, because we were called (with	@args)\n";
	}, 'xyz');

       which is	much the same as:

	my $code = do {
	 my $sub = sub {
	  my ($self, @args) = @_;
	  print	"$self must still be alive, because we were called (with @args)\n";
	 };
	 Scalar::Util::weaken(my $weak_obj = $self);
	 sub {
	  return unless	$weak_obj; # in	case it	already	went away
	  $sub->($weak_obj, 'xyz', @_);
	 }
	};

       There's an equivalent - but somewhat less useful	-  $curry  package
       variable:

	use curry;

	my $code = $self->$curry::curry(sub {
	 my ($self, $var) = @_;
	 print "The stashed value from our ->something method call was $var\n";
	}, $self->something('complicated'));

       Both of these methods can also be used if your scalar is	a method name,
       rather than a coderef.

	use curry;

	my $code = $self->$curry::curry($methodname, $self->something('complicated'));

RATIONALE
       How many	times have you written

	 sub { $obj->something($some, $args, @_) }

       or worse	still needed to	weaken it and had to check and re-check	your
       code to be sure you weren't closing over	things the wrong way?

       Right. That's why I wrote this.

AUTHOR
       mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>

CONTRIBUTORS
       None yet	- maybe	this software is perfect! (ahahahahahahahahaha)

COPYRIGHT
       Copyright (c) 2012 the curry "AUTHOR" and "CONTRIBUTORS"	as listed
       above.

LICENSE
       This library is free software and may be	distributed under the same
       terms as	perl itself.

perl v5.24.1			  2017-06-23			      curry(3)

NAME | SYNOPSIS | RATIONALE | AUTHOR | CONTRIBUTORS | COPYRIGHT | LICENSE

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