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indirect-0.15
River stage two • 60 direct dependents • 74 total dependents
9 ++
/ indirect

NAME

indirect - Lexically warn about using the indirect object syntax.

VERSION

Version 0.15

SYNOPSIS

    # In a script
    no indirect;
    my $x = new Apple 1, 2, 3; # warns
    {
     use indirect;
     my $y = new Pear; # ok
     {
      no indirect hook => sub { die "You really wanted $_[0]\->$_[1] at $_[2]:$_[3]" };
      my $z = new Pineapple 'fresh'; # croaks 'You really wanted Pineapple->new at blurp.pm:13'
     }
    }
    no indirect ':fatal';
    if (defied $foo) { ... } # croaks, note the typo

    # From the command-line
    perl -M-indirect -e 'my $x = new Banana;' # warns

    # Or each time perl is ran
    export PERL5OPT="-M-indirect"
    perl -e 'my $y = new Coconut;' # warns

DESCRIPTION

When enabled (or disabled as some may prefer to say, since you actually turn it on by calling no indirect), this pragma warns about indirect object syntax constructs that may have slipped into your code. This syntax is now considered harmful, since its parsing has many quirks and its use is error prone (when swoosh isn't defined, swoosh $x actually compiles to $x->swoosh).

It currently does not warn when the object is enclosed between braces (like meth { $obj } @args) or for core functions (print or say). This may change in the future, or may be added as optional features that would be enabled by passing options to unimport.

This module is not a source filter.

METHODS

unimport [ hook => $hook | ':fatal' ]

Magically called when no indirect @opts is encountered. Turns the module on. The policy to apply depends on what is first found in @opts :

  • If it's the string ':fatal', the compilation will croak on the first indirect syntax met.

  • If the key/value pair hook => $hook comes first, $hook will be called for each error with the object name as $_[0], the method name as $_[1], the current file as $_[2] and the line number as $_[3].

  • Otherwise, a warning will be emitted for each indirect construct.

import

Magically called at each use indirect. Turns the module off.

CONSTANTS

I_THREADSAFE

True iff the module could have been built with thread-safety features enabled.

CAVEATS

The implementation was tweaked to work around several limitations of vanilla perl pragmas : it's thread safe, and doesn't suffer from a perl 5.8.x-5.10.0 bug that causes all pragmas to propagate into required scopes.

meth $obj (no semicolon) at the end of a file won't be seen as an indirect object syntax, although it will as soon as there is another token before the end (as in meth $obj; or meth $obj 1).

With 5.8 perls, the pragma does not propagate into eval STRING. This is due to a shortcoming in the way perl handles the hints hash, which is addressed in perl 5.10.

DEPENDENCIES

perl 5.8.

XSLoader (standard since perl 5.006).

AUTHOR

Vincent Pit, <perl at profvince.com>, http://www.profvince.com.

You can contact me by mail or on irc.perl.org (vincent).

BUGS

Please report any bugs or feature requests to bug-indirect at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=indirect. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

    perldoc indirect

Tests code coverage report is available at http://www.profvince.com/perl/cover/indirect.

ACKNOWLEDGEMENTS

Bram, for motivation and advices.

COPYRIGHT & LICENSE

Copyright 2008-2009 Vincent Pit, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.