README

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    JavaScript::SpiderMonkey
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NAME
    JavaScript::SpiderMonkey - Perl interface to the JavaScript Engine

SYNOPSIS
        use JavaScript::SpiderMonkey;

        my $js = JavaScript::SpiderMonkey->new();

        $js->init();  # Initialize Runtime/Context

                      # Define a perl callback for a new JavaScript function
        $js->function_set("print_to_perl", sub { print "@_\n"; });

                      # Create a new (nested) object and a property
        $js->property_by_path("document.location.href");

                      # Execute some code
        my $rc = $js->eval(q!
            document.location.href = append("http://", "www.aol.com");

            print_to_perl("URL is ", document.location.href);

            function append(first, second) {
                 return first + second;
            }
        !);

            # Get the value of a property set in JS
        my $url = $js->property_get("document.location.href");

        $js->destroy();

INSTALL
    JavaScript::SpiderMonkey requires Mozilla's readily compiled
    SpiderMonkey 1.6 distribution or better. Please check "SpiderMonkey
    Installation".

DESCRIPTION
    JavaScript::SpiderMonkey is a Perl Interface to the SpiderMonkey
    JavaScript Engine. It is different from Claes Jacobsson's
    "JavaScript.pm" in that it offers two different levels of access:

    [1] A 1:1 mapping of the SpiderMonkey API to Perl

    [2] A more Perl-like API

    This document describes [2], for [1], please check "SpiderMonkey.xs".

  new()
    "$js = JavaScript::SpiderMonkey->new()" creates a new object to work
    with. To initialize the JS runtime, call "$js->init()" afterwards.

  $js->destroy()
    "$js->destroy()" destroys the current runtime and frees up all memory.

  $js->init()
    "$js->init()" initializes the SpiderMonkey engine by creating a context,
    default classes and objects and adding an error reporter.

  $js->array_by_path($name)
    Creates an object of type *Array* in the JS runtime:

        $js->array_by_path("document.form");

    will first create an object with the name "document" (unless it exists
    already) and then define a property named "form" to it, which is an
    object of type *Array*. Therefore, in the JS code, you're going to be
    able define things like

        document.form[0] = "value";

  $js->function_set($name, $funcref, [$obj])
    Binds a Perl function provided as a coderef ($funcref) to a newly
    created JS function named $name in JS land. It's a real function
    (therefore bound to the global object) if $obj is omitted. However, if
    $obj is ref to a JS object (retrieved via "$js->object_by_path($path)"
    or the like), the function will be a *method* of the specified object.

        $js->function_set("write", sub { print @_ });
            # write("hello"); // In JS land

        $obj = $j->object_by_path("navigator");
        $js->function_set("write", sub { print @_ }, $obj);
            # navigator.write("hello"); // In JS land

  $js->array_set_element($obj, $idx, $val)
    Sets the element of the array $obj at index position $idx to the value
    $val. $obj is a reference to an object of type array (retrieved via
    "$js->object_by_path($path)" or the like).

  $js->array_set_element_as_object($obj, $idx, $elobj)
    Sets the element of the array $obj at index position $idx to the object
    $elobj (both $obj and $elobj have been retrieved via
    "$js->object_by_path($path)" or the like).

  $js->array_get_element($obj, $idx)
    Gets the value of of the element at index $idx of the object of type
    Array $obj.

  $js->property_by_path($path, $value, [$getter], [$setter])
    Sets the specified property of an object in $path to the value $value.
    $path is the full name of the property, including the object(s) in JS
    land it belongs to:

        $js-E<gt>property_by_path("document.location.href", "abc");

    This first creates the object "document" (if it doesn't exist already),
    then the object "document.location", then attaches the property "href"
    to it and sets it to "abc".

    $getter and $setter are coderefs that will be called by the JavaScript
    engine when the respective property's value is requested or set:

        sub getter {
            my($property_path, $value) = @_;
            print "$property_path has value $value\n";
        }

        sub setter {
            my($property_path, $value) = @_;
            print "$property_path set to value $value\n";
        }

        $js-E<gt>property_by_path("document.location.href", "abc",
                                  \&getter, \&setter);

    If you leave out $getter and $setter, there's going to be no callbacks
    triggerd while the properity is set or queried. If you just want to
    specify a $setter, but no $getter, set the $getter to "undef".

  $js->object_by_path($path, [$newobj])
    Get a pointer to an object with the path specified. Create it if it's
    not there yet. If $newobj is provided, the ref is used to bind the
    existing object to the name in $path.

  $js->property_get($path)
    Fetch the property specified by the $path.

        my $val = $js->property_get("document.location.href");

  $js->eval($code)
    Runs the specified piece of <$code> in the JS engine. Afterwards,
    property values of objects previously defined will be available via
    "$j->property_get($path)" and the like.

        my $rc = $js->eval("write('hello');");

    The method returns 1 on success or else if there was an error in JS
    land. In case of an error, the JS error text will be available in $@.

SpiderMonkey Installation
    First, get the latest SpiderMonkey distribution from mozilla.org:
    http://ftp.mozilla.org/pub/spidermonkey/releases/ shows which releases are
    available. "js-1.60.tar.gz" has been proven to work.

    Untar it at the same directory level as you just untarred the
    "JavaScript::SpiderMonkey" distribution you're currently reading. So, if
    you're currently in "/my/path/JavaScript-SpiderMonkey-v.vv", do this:

        cp js-1.60.tar.gz /my/path
        cd /my/path
        tar zxfv js-1.60.tar.gz

    Then, compile the SpiderMonkey distribution, if you're on Linux, just
    use:

        cd js/src
        make -f Makefile.ref

    It's important that the js and JavaScript-SpiderMonkey-v.vv directories
    are at the same level:

        [/my/path]$ ls
        JavaScript-SpiderMonkey-v.vv
        js
        js-1.60.tar.gz
        [/my/path]$

    (Note that you *can* untar the SpiderMonkey distribution elsewhere, but,
    if so, then you need to edit the setting of $JSLIBPATH in Makefile.PL).

    Next, you need to copy the shared library file thus constructed (e.g.,
    libjs.so or js32.dll) to an appropriate directory on your library path.
    On Windows, this can also be the directory where the perl executable
    lives. On Unix, this has been shown to work without copying, but this
    way you need to keep the compiled binary in the "js" build directory
    forever. Copying "js/src/Your_OS_DBG.OBJ/libjs.so" to "/usr/local/lib"
    and making sure that "/usr/local/lib" is in your "LD_LIBRARY_PATH" seems
    to be safest bet.

    Now, build JavaScript::SpiderMonkey in the standard way:

        cd JavaScript-SpiderMonkey-v.vv
        perl Makefile.PL
        make
        make test
        make install

AUTHORS 
    Mike Schilli
    Thomas Busch

COPYRIGHT AND LICENSE
    Copyright (c) 2002-2005 Mike Schilli
    Copyright (c) 2006-2018 Thomas Busch

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