1Throwable(3) User Contributed Perl Documentation Throwable(3)
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6 Throwable - a role for classes that can be thrown
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9 version 1.001
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12 package Redirect;
13 # NOTE: Moo can also be used here instead of Moose
14 use Moose;
15 with 'Throwable';
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17 has url => (is => 'ro');
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19 ...then later...
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21 Redirect->throw({ url => $url });
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24 Throwable is a role for classes that are meant to be thrown as
25 exceptions to standard program flow. It is very simple and does only
26 two things: saves any previous value for $@ and calls "die $self".
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28 Throwable is implemented with Moo, so you can stick to Moo or use
29 Moose, as you prefer.
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32 This library should run on perls released even a long time ago. It
33 should work on any version of perl released in the last five years.
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35 Although it may work on older versions of perl, no guarantee is made
36 that the minimum required version will not be increased. The version
37 may be increased for any reason, and there is no promise that patches
38 will be accepted to lower the minimum required perl.
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41 previous_exception
42 This attribute is created automatically, and stores the value of $@
43 when the Throwable object is created. This is done on a best effort
44 basis. $@ is subject to lots of spooky action-at-a-distance. For now,
45 there are clearly ways that the previous exception could be lost.
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48 throw
49 Something::Throwable->throw({ attr => $value });
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51 This method will call new, passing all arguments along to new, and will
52 then use the created object as the only argument to "die".
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54 If called on an object that does Throwable, the object will be
55 rethrown.
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57 new_with_previous
58 die Something::Throwable->new_with_previous({ attr => $value });
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60 Constructs an exception object and return it, while trying to make sure
61 that any values in $@ are safely stored in "previous_exception" without
62 being stomped by evals in the construction process.
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64 This is more reliable than calling "new" directly, but doesn't include
65 the forced "die" in "throw".
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68 • Ricardo SIGNES <cpan@semiotic.systems>
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70 • Florian Ragwitz <rafl@debian.org>
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73 • Arthur Axel 'fREW' Schmidt <frioux@gmail.com>
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75 • Brian Manning <brian@xaoc.org>
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77 • Brian Manning <xaoc@cpan.org>
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79 • Christian Walde <walde.christian@googlemail.com>
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81 • Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
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83 • Dave Rolsky <autarch@urth.org>
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85 • David E. Wheeler <david@justatheory.com>
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87 • Graham Knop <haarg@haarg.org>
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89 • Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>
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91 • Justin Hunter <justin.d.hunter@gmail.com>
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93 • Matt S Trout <mst@shadowcat.co.uk>
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95 • Olaf Alders <olaf@wundersolutions.com>
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97 • Ricardo Signes <rjbs@semiotic.systems>
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99 • Toby Inkster <mail@tobyinkster.co.uk>
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102 This software is copyright (c) 2022 by Ricardo SIGNES.
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104 This is free software; you can redistribute it and/or modify it under
105 the same terms as the Perl 5 programming language system itself.
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109perl v5.38.0 2023-07-21 Throwable(3)