NAME

       Sub::Defer - Defer generation of subroutines until they are first called

SYNOPSIS

        use Sub::Defer;

        my $deferred = defer_sub 'Logger::time_since_first_log' => sub {
           my $t = time;
           sub { time - $t };
        };

         Logger->time_since_first_log; # returns 0 and replaces itself
         Logger->time_since_first_log; # returns time - $t

DESCRIPTION

       These subroutines provide the user with a convenient way to defer creation of subroutines
       and methods until they are first called.

SUBROUTINES

   defer_sub
        my $coderef = defer_sub $name => sub { ... }, \%options;

       This subroutine returns a coderef that encapsulates the provided sub - when it is first
       called, the provided sub is called and is -itself- expected to return a subroutine which
       will be goto'ed to on subsequent calls.

       If a name is provided, this also installs the sub as that name - and when the subroutine
       is undeferred will re-install the final version for speed.

       Exported by default.

       Options

       A hashref of options can optionally be specified.

       package
           The package to generate the sub in.  Will be overridden by a fully qualified $name
           option.  If not specified, will default to the caller's package.

       attributes
           The "Subroutine Attributes" in perlsub to apply to the sub generated.  Should be
           specified as an array reference.

   undefer_sub
        my $coderef = undefer_sub \&Foo::name;

       If the passed coderef has been deferred this will "undefer" it.  If the passed coderef has
       not been deferred, this will just return it.

       If this is confusing, take a look at the example in the "SYNOPSIS".

       Exported by default.

   defer_info
        my $data = defer_info $sub;
        my ($name, $generator, $options, $undeferred_sub) = @$data;

       Returns original arguments to defer_sub, plus the undeferred version if this sub has
       already been undeferred.

       Note that $sub can be either the original deferred version or the undeferred version for
       convenience.

       Not exported by default.

   undefer_all
        undefer_all();

       This will undefer all deferred subs in one go.  This can be very useful in a forking
       environment where child processes would each have to undefer the same subs.  By calling
       this just before you start forking children you can undefer all currently deferred subs in
       the parent so that the children do not have to do it.  Note this may bake the behavior of
       some subs that were intended to calculate their behavior later, so it shouldn't be used
       midway through a module load or class definition.

       Exported by default.

   undefer_package
         undefer_package($package);

       This undefers all deferred subs in a package.

       Not exported by default.

SUPPORT

       See Sub::Quote for support and contact information.

AUTHORS

       See Sub::Quote for authors.

COPYRIGHT AND LICENSE

       See Sub::Quote for the copyright and license.