package Specio::DeclaredAt;

use strict;
use warnings;

our $VERSION = '0.48';

use Specio::OO;

    my $attrs = {
        package => {
            isa      => 'Str',
            required => 1,
        filename => {
            isa      => 'Str',
            required => 1,
        line => {
            isa      => 'Int',
            required => 1,
        subroutine => {
            isa       => 'Str',
            predicate => 'has_subroutine',

    ## no critic (Subroutines::ProhibitUnusedPrivateSubroutines)
    sub _attrs {
        return $attrs;

sub new_from_caller {
    my $class = shift;
    my $depth = shift;

    my %p;
    @p{qw( package filename line )} = ( caller($depth) )[ 0, 1, 2 ];

    my $sub = ( caller( $depth + 1 ) )[3];
    $p{subroutine} = $sub if defined $sub;

    return $class->new(%p);

sub description {
    my $self = shift;

    my $package  = $self->package;
    my $filename = $self->filename;
    my $line     = $self->line;

    my $desc = "declared in package $package ($filename) at line $line";
    if ( $self->has_subroutine ) {
        $desc .= ' in sub named ' . $self->subroutine;

    return $desc;



# ABSTRACT: A class to represent where a type or coercion was declared



=encoding UTF-8

=head1 NAME

Specio::DeclaredAt - A class to represent where a type or coercion was declared

=head1 VERSION

version 0.48


    my $declared = Specio::DeclaredAt->new_from_caller(1);

    print $declared->description;


This class provides a thin wrapper around some of the return values from Perl's
C<caller> built-in. It's used internally to identify where types and coercions
are being declared, which is useful when generating error messages.

=head1 API

This class provides the following methods.

=head2 Specio::DeclaredAt->new_from_caller($depth)

Given a call stack depth, this method returns a new C<Specio::DeclaredAt>

=head2 $declared_at->package, $declared_at->filename, $declared_at->line

Returns the call stack information recorded when the object was created. These
values are always populated.

=head2 $declared_at->subroutine

Returns the subroutine from the call stack. This may be an C<udnef>

=head2 $declared_at->has_subroutine

Returns true if there is a subroutine name associated with this object.

=head2 $declared_at->description

Puts all the information together into a single string like "declared in
package Foo::Bar (.../Foo/ at line 42 in sub named blah".

=head1 SUPPORT

Bugs may be submitted at L<>.

=head1 SOURCE

The source code repository for Specio can be found at L<>.

=head1 AUTHOR

Dave Rolsky <>


This software is Copyright (c) 2012 - 2022 by Dave Rolsky.

This is free software, licensed under:

  The Artistic License 2.0 (GPL Compatible)

The full text of the license can be found in the
F<LICENSE> file included with this distribution.