NAME

JavaScript::Context - An object in which we can execute JavaScript

SYNOPSIS

use JavaScript;

# Create a runtime and a context
my $rt = JavaScript::Runtime->new();
my $cx = $rt->create_context();

# Add a function which we can call from JavaScript
$cx->bind_function(print => sub { print @_; });

my $result = $cx->eval($source);

INTERFACE

INSTANCE METHODS

bind_class ( %args )

Defines a new class that can be used from JavaScript in the contet.

It expects the following arguments

name

The name of the class in JavaScript.

name => "MyPackage",

constructor

A reference to a subroutine that returns the Perl object that represents the JavaScript object. If omitted a default constructor will be supplied that calls the method new on the defined package (or name if no package is defined).

constructor => sub { MyPackage->new(@_); },

package

The name of the Perl package that represents this class. It will be passed as first argument to any class methods and also used in the default constructor.

package => "My::Package",

methods (fs)

A hash reference of methods that we define for instances of the class. In JavaScript this would be o = new MyClass(); o.method().

The key is used as the name of the function and the value should be either a reference to a subroutine or the name of the Perl subroutine to call.

methods => { to_string => \&My::Package::to_string,
             random    => "randomize"
}

static_methods (static_ps)

Like fs but these are called on the class itself. In JavaScript this would be MyClass.method().

properties (ps)

A hash reference of properties that we define for instances of the class. In JavaScript this would be o = new MyClass(); f = o.property;

The key is used as the name of the property and the value is used to specify what method to call as a get-operation and as a set-operation. These can either be specified using references to subroutines or name of subroutines. If the getter is undefined the property will be write-only and if the setter is undefined the property will be read-only. You can specify the getter/setter using either an array reference, [\&MyClass::get_property, \&MyClass::set_property], a string, "MyClass::set_property MyClass::get_property" or a hash reference, { getter = "MyClass::get_property", setter => "MyClass::set_property" }>.

ps => { length => [qw(get_length)],
        parent => { getter => \&MyClass::get_parent, setter => \&MyClass::set_parent },
      }

static_properties (static_ps)

Like ps but these are defined on the class itself. In JavaScript this would be f = MyClass.property.

flags

A bitmask of attributes for the class. Valid attributes are:

JS_CLASS_NO_INSTANCE

Makes the class throw an exception if JavaScript tries to instansiate the class.

bind_function ( name => $name, func => $subroutine )

bind_function ( $name => $subroutine )

Defines a Perl subroutine ($subroutine_ref) as a native function with the given $name. The argument $subroutine can either be the name of a subroutine or a reference to one.

bind_object ( $name => $object )

Binds a Perl object to the context under a given name.

bind_value ( $name => $value )

Defines a value with a given name and value. Trying to redefine an already existing property throws an exception.

unbind_value ( $name )

Removed a property from the context or a specified object.

call ( $name, @arguments )

call ( $function, @arguments )

Calls a function with the given name $name or the JavaScript::Function-object $function and passes the rest of the arguments to the JavaScript function.

can ( $name )

Returns true if there is a function with a given $name, otherwise it returns false.

compile ( $source )

Pre-compiles the JavaScript given in $source and returns a JavaScript::Script-object that can be executed over and over again. If an error occures because of a compilation error it returns undef and $@ is set.

eval ( $source )

Evaluates the JavaScript code given in $source and returns the result from the last statement.

If there is a compilation error (such as a syntax error) or an uncaught exception is thrown in JavaScript this method returns undef and $@ is set.

eval_file ( $path )

Evaluates the JavaScript code in the file specified by $path and returns the result from the last statement.

If there is a compilation error (such as a syntax error) or an uncaught exception is thrown in JavaScript this method returns undef and $@ is set.

find ( $native_context )

Returns the JavaScript::Context-object associated with a given native context.

set_branch_handler ( $handler )

Attaches an branch callback handler (a function that is called when a branch is performed) to the context. The argument $handler may be a code-reference or the name of a subroutine.

To remove the handler call this method with an undefined argument.

The handler is called when a script branches backwards during execution, when a function returns and the end of the script. To continue execution the handler must return a true value. To abort execution either throw an exception or return a false value.

get_version ( )

Returns the runtime version of the context as a string, for exmaple 1.7 or or ECMAv3.

set_version ( $version )

Sets the runtime version of the context to that specified in the string $version. Some features such as let and yield might not be enabled by default and thus must be turned on by specifying what JS version we're using.

A list of these can be found at http://developer.mozilla.org/en/docs/JSVersion but may vary depending on the version of your runtime.