oracular (3) goto::file.3pm.gz

Provided by: libgoto-file-perl_0.005-2_all bug

NAME

       goto::file - Stop parsing the current file and move on to a different one.

DESCRIPTION

       It is rare, but there are times where you want to swap out the currently compiling file for a different
       one. This module does that. From the point you "use" the module perl will be parsing the new file instead
       of the original.

WHY?!

       This was created specifically for Test2::Harness which can preload modules and fork to run each test. The
       problem was that using "do" to execute the test files post-fork was resuling in extra frames in the stack
       trace... in other words there are a lot of tests that assume the test file is the bottom of the stack.
       This happens all the time, specially if stack traces need to be verified.

       This module allows Test2::Harness to swap out the main script for the new file without adding a stack
       frame.

SYNOPSIS

       Plain and simple:

           #!/usr/bin/perl

           use goto::file 'some_file.pl';

           die "This will never be seen!";

           __DATA__

           This data will not be seen by <DATA>

       More useful:

           #!/usr/bin/perl

           BEGIN {
               my $file = should_switch_files();

               if ($file) {
                   print "about to switch to file '$file'\n";
                   require goto::file;
                   goto::file->import($file);
               }
           }

           print "Did not go to a file\n";

       Another thing you can do:

           use goto::file [
               'print "Hi!\n";',
               "exit 0",
           ];

           die "Will not get here";

NOTES

       __DATA__ and <DATA>
           This module does its very best to make sure the data you get from <DATA> comes from the NEW file, and
           not the old. At the moment there are no known failure cases, but there could be some.

IMPLEMENTATION DETAILS

       This is a source filter. The source filter simply disgards the lines from the original file and instead
       feeds perl lines from the new file. There is also a small source injection at the start that sets up
       "<DATA>" and makes sure line numbers and file name are all correct.

SOURCE

       The source code repository for goto-file can be found at http://github.com/exodist/goto-file/.

MAINTAINERS

       Chad Granum <exodist@cpan.org>

AUTHORS

       Chad Granum <exodist@cpan.org>

       Copyright 2017 Chad Granum <exodist7@gmail.com>.

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

       See http://dev.perl.org/licenses/