# JavaScript-Shell **Repository Path**: mirrors_gitpan/JavaScript-Shell ## Basic Information - **Project Name**: JavaScript-Shell - **Description**: Read-only release history for JavaScript-Shell - **Primary Language**: Unknown - **License**: Not specified - **Default Branch**: master - **Homepage**: None - **GVP Project**: No ## Statistics - **Stars**: 0 - **Forks**: 0 - **Created**: 2020-10-20 - **Last Updated**: 2025-09-21 ## Categories & Tags **Categories**: Uncategorized **Tags**: None ## README =pod =head1 NAME JavaScript::Shell - Run Spidermonkey shell from Perl =head1 SYNOPSIS use JavaScript::Shell; use strict; use warnings; my $js = JavaScript::Shell->new(); ##create context my $ctx = $js->createContext(); $ctx->Set('str' => 'Hello'); $ctx->Set('getName' => sub { my $context = shift; my $args = shift; my $firstname = $args->[0]; my $lastname = $args->[1]; return $firstname . ' ' . $lastname; }); $ctx->eval(qq! function message (){ var name = getName.apply(this,arguments); var welcome_message = str; return welcome_message + ' ' + name; } !); my $val = $ctx->get('message' => 'Mamod', 'Mehyar')->value; print $val . "\n"; ## prints 'Hello Mamod Mehyar' $js->destroy(); =head1 DESCRIPTION JavaScript::Shell will turn Spidermonkey shell to an interactive environment by connecting it to perl It will let you bind functions from perl and call them from javascript or create functions in javascript then call them from perl =head1 WHY While I was working on a project where I needed to connect perl with javascript I had a lot of problems with existing javascript modules, they were eaither hard to compile or out of date, and since I don't know C/C++ - creating my own perl / javascript binding wasn't an option, so I thought of this approach as an alternative. Even though this sounds crazy to do, to my surprise it worked as expected - at least in my usgae cases =head1 SPEED JavaScript::Shell connect spidermonkey with perl through IPC bridge using L so execution speed will never be as fast as using C/C++ bindings ported to perl directly There is another over head when translating data types to/from perl, since it converts perl data to JSON & javascript JSON to perl data back again. Saying that the over all speed is acceptable and you can take some steps to improve speed like =over 4 =item L Make sure you have L installed - this is important, JavaScript::Shell uses JSON::Any to parse data and it will use any available JSON parser but if you have JSON::XS installed in your system it will use it by default as it's the fastest JSON parser available =item Data Transfer Try to transfer small data chunks between processes when possible, sending large data will be very slow =item Minimize calls Minimize number of calls to both ends, let each part do it's processing for eaxmple: ##instead of $js->eval(qq! function East (){} function West (){} function North (){} function South (){} !); $js->call('East'); $js->call('West'); $js->call('North'); $js->call('South'); ##do this $js->eval(qq! function all () { East(); West(); North(); South(); } function East (){} function west (){} function North (){} function South (){} !); $js->call('all'); =back =head1 CONTEXT Once you intiate JavaScript::Shell you can create as many contexts as you want, each context will has it's own scope and will not overlap with other created contexts. my $js = JavaScript::Shell->new(); my $ctx = $js->createContext(); You can pass a hash ref with simple data to C method as a sandbox object and will be copied to the context immediately my $ctx->createContext({ Foo => 'Bar', Foo2 => 'Bar2' }); =head1 FUNCTIONS =head2 new Initiates SpiderMonkey Shell =head2 createContext creates a new context =head2 run This will run javascript code in a blocking loop until you call jshell.endLoop() from your javascript code $js->Set('Name' => 'XXX'); $js->eval(qq! for (var i = 0; i < 100; i++){ } jshell.endLoop(); !); $js->run(); ##will never reach this point unless we call ## jshell.endLoop(); in javascript code as above =head2 Set Sets/Defines javascript variables, objects and functions from perl ## set variable 'str' with Hello vales $ctx->Set('str' => 'Hello'); ## set 'arr' Array Object [1,2,3,4] $ctx->Set('arr' => [1,2,3,4]); ## set Associated Array Object $ctx->Set('obj' => { str1 => 'something', str2 => 'something ..' }); ## set 'test' function ## caller will pass 2 arguments ## 1- context object ## 2- array ref of all passed arguments $ctx->Set('test' => sub { my $context = shift; my $args = shift; return $args->[0] . ' ' . $args->[1]; }); ## javascript object creation style $ctx->Set('obj' => {}); #then $ctx->Set('obj.name' => 'XXX'); $ctx->Set('obj.get' => sub { }); ... =head2 get get values from javascript code, returns a C Object my $ret = $ctx->get('str'); print $ret->value; ## Hello ## remember to call value to get the returned string/object get method will search your context for a matched variable/object/function and return it's value, if the name was detected for a function in will run this function first and then returns it's return value $ctx->get('obj.name')->value; ## XXX ##you can pass variables when trying to get a function $ctx->get('test' => 'Hi','Bye')->value; ## Hi Bye ##get an evaled script values $ctx->get('eval' => qq! var n = 2; var x = 3; n+x; !)->value; #--> 5 =head2 call Calling javascript functions from perl, same as C but doesn't return any value $ctx->call('test'); =head2 eval eval javascript code $ctx->eval(qq! //javascript code var n = 10; for(var i = 0; i<100; i++){ n += 10; } ... !); =head2 onError set error handler method, this method accepts a code ref only. When an error raised from javascript this code ref will be called with 2 arguments =over 4 =item * JavaScript::Shell instance =item * error object - Hash ref =back Error Hash has the folloing keys =over 4 =item * B I =item * B I =item * B I =item * B I =item * B I =back Setting error hnadler example my $js = JavaScript::Shell->new(); $js->onError(sub{ my $self = shift; my $error = shift; print STDERR $error->{message} . ' at ' . $error->{line} exit(0); }); =head2 destroy Destroy javascript shell / clear context my $js = JavaScript::Shell->new(); my $ctx->createContext(); ##clear context; $ctx->destroy(); ##close spidermonkey shell $js->destroy(); =head1 LICENSE This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.16.2 or, at your option, any later version of Perl 5 you may have available. =head1 COPYRIGHTS Copyright (C) 2013 by Mamod A. Mehyar =cut