curry
curry(3pm) User Contributed Perl Documentation curry(3pm)
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 v5.26.1 2018-01-21 curry(3pm)
Man Pages Copyright Respective Owners. Site Copyright (C) 1994 - 2024
Hurricane Electric.
All Rights Reserved.