X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FFunction%2FParameters.pm;h=62db745a2788f901963963fc64db614aec13c709;hb=5e074131c84a5e52e7d8da01c16d2ac1cf303621;hp=4bcec7e94b0809302c309ddf265ebaf1aec2cdf2;hpb=096dbcecd7c2a600af8aa92c236dbc96b59373ca;p=p5sagit%2FFunction-Parameters.git

diff --git a/lib/Function/Parameters.pm b/lib/Function/Parameters.pm
index 4bcec7e..62db745 100644
--- a/lib/Function/Parameters.pm
+++ b/lib/Function/Parameters.pm
@@ -155,6 +155,50 @@ sub unimport {
 }
 
 
+our %metadata;
+
+sub _register_info {
+	my (
+		$key,
+		$declarator,
+		$invocant,
+		$positional_required,
+		$positional_optional,
+		$named_required,
+		$named_optional,
+		$slurpy,
+	) = @_;
+
+	my $blob = pack '(Z*)*',
+		$declarator,
+		$invocant // '',
+		join(' ', @$positional_required),
+		join(' ', @$positional_optional),
+		join(' ', @$named_required),
+		join(' ', @$named_optional),
+		$slurpy // '',
+	;
+
+	$metadata{$key} = $blob;
+}
+
+sub info {
+	my ($func) = @_;
+	my $key = _cv_root $func or return undef;
+	my $blob = $metadata{$key} or return undef;
+	my @info = unpack '(Z*)*', $blob;
+	require Function::Parameters::Info;
+	Function::Parameters::Info->new(
+		keyword => $info[0],
+		invocant => $info[1] || undef,
+		_positional_required => [split ' ', $info[2]],
+		_positional_optional => [split ' ', $info[3]],
+		_named_required => [split ' ', $info[4]],
+		_named_optional => [split ' ', $info[5]],
+		slurpy => $info[6] || undef,
+	)
+}
+
 'ok'
 
 __END__
@@ -569,6 +613,19 @@ C<< use Function::Parameters { fun => 'function', method => 'method' } >>.
 C<use Function::Parameters qw(:strict)> is equivalent to
 C<< use Function::Parameters { fun => 'function_strict', method => 'method_strict' } >>.
 
+=head2 Introspection
+
+You can ask a function at runtime what parameters it has. This functionality is
+available through the function C<Function::Parameters::info> (which is not
+exported, so you have to call it by its full name). It takes a reference to a
+function, and returns either C<undef> (if it knows nothing about the function)
+or a L<Function::Parameters::Info> object describing the parameter list.
+
+Note: This feature is implemented using L<Moo>, so you'll need to have L<Moo>
+installed if you want to call C<Function::Parameters::info>.
+
+See L<Function::Parameters::Info> for examples.
+
 =head2 Wrapping C<Function::Parameters>
 
 If you want to write a wrapper around C<Function::Parameters>, you only have to
@@ -599,6 +656,10 @@ generated code corresponds to:
   # ... turns into ...
   sub bar :method { my $self = shift; my ($x, $y, @z) = @_; sub bar; ... }
 
+=head1 SEE ALSO
+
+L<Function::Parameters::Info>
+
 =head1 AUTHOR
 
 Lukas Mai, C<< <l.mai at web.de> >>