NAME
JavaScript::V8 - Perl interface to the V8 JavaScript engine
SYNOPSIS
use JavaScript::V8;
my $context = JavaScript::V8::Context->new();
$context->bind( write => sub { print @_ } );
$context->bind( bottles => 3 );
$context->bind( wine_type => ['red', 'white', 'sparkling'] );
$context->bind( wine_type_description => {
white => "White wine is a wine whose color is slightly yellow. This kind of wine is produced using non-coloured grapes or using red-skinned grapes' juice, not allowing it to extract pigment from the skin.",
red => "Red wine is a type of wine made from dark-coloured (black) grape varieties. The actual colour of the wine can range from intense violet, typical of young wines, through to brick red for mature wines and brown for older red wines.",
sparkling => "Sparkling wine is a wine with significant levels of carbon dioxide in it making it fizzy. The carbon dioxide may result from natural fermentation, either in a bottle, as with the méthode champenoise, in a large tank designed to withstand the pressures involved (as in the Charmat process), or as a result of carbon dioxide injection.",
});
$context->eval(q/
for (i = bottles; i > 0; i--) {
var type = wine_type[i - 1];
var description = wine_type_description[type];
write(i + " bottle(s) of wine on the wall, " + i + " bottle(s) of wine\n");
write("This is bottle of " + type + " wine. " + description + "\n\n");
write("Take 1 down, pass it around, ");
if (i > 1) {
write((i - 1) + " bottle(s) of wine on the wall.\n");
}
else {
write("No more bottles of wine on the wall!\n");
}
}
/);
DIRECTION
v8's interface and behaviour changes a lot. Updating this module to support newer versions of v8 is a big job. The module currently supports v8 6.2.
The dramatic API changes mean that backward compatibility with the current API will be effectively impossible. The likelihood of security holes in a library as large, complex and high-profile as V8 means means it will be necessary to keep up with the current version, rather than with the one that this module supports.
Therefore, the next steps will be to use the excellent Alien::Build to make an "alien" module that builds and makes available v8. The current Alien::V8 is not suitable, since its last release was from 2011.
Contributions of effort will be welcome. Please open an RT, or just #v8
on irc.perl.org
to get involved.
Google maintains a public document describing v8's API changes: https://docs.google.com/document/d/1g8JFi8T_oAE_7uAri7Njtig7fKaPDfotU6huOa1alds/edit#
INSTALLING V8
Memory notes
Please note that v8 needs around 2MB of VSZ memory. See https://rt.cpan.org/Ticket/Display.html?id=78512 for more information.
From Source
See https://v8.dev/docs/build for how. Be warned, the source repo alone is over 800MB.
On OS X
On OS X I've successfully used Homebrew, install Homebrew then:
brew install v8
Binary
Linux
On Ubuntu 22.04 (and possibly Debian), the library and header files can be installed by running:
sudo aptitude install libnode-dev
V8_DIR=/usr/include/nodejs/deps/v8 perl Makefile.PL
since the NodeJS package includes v8 version 7.8 (at the time of writing, Dec 2022).
Similar packages may be available for other distributions (adjust the package names accordingly).
SEE ALSO
Further documentation
-
Details on the context object and the mapping between JavaScript and Perl types.
Extension modules
Other JavaScript bindings for Perl
REPOSITORY
The source code lives at http://github.com/dgl/javascript-v8.
AUTHORS
Pawel Murias <pawelmurias at gmail dot com>
David Leadbeater <dgl@dgl.cx>
Paul Driver <frodwith at gmail dot com>
Igor Zaytsev <igor.zaytsev@gmail.com>
COPYRIGHT AND LICENSE
Copyright (c) 2009-2010 Paweł Murias
Copyright (c) 2011 David Leadbeater
Copyright (c) 2011 Igor Zaytsev
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
ACKNOWLEDGMENTS
- Claes Jakobsson <claesjac at cpan dot org>
-
I stole and adapted pieces of docs and API design from JavaScript.pm
- Brian Hammond <brain @ fictorial dot com>
-
For salvaging the code of V8.pm from a message board (which I took some code and the idea from)
- The hacker who wrote V8.pm and posted it on the message board
- All the fine people at #perl@freenode.org for helping me write this module