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JE::LValue
JavaScript lvalue class

JE::LValue - JavaScript lvalue class


NAME

JE::LValue - JavaScript lvalue class


SYNOPSIS


  use JE::LValue;

  $lv = new JE::LValue $some_obj, 'property_name';

  $lv->get;         # get property

  $lv->set($value)  # set property

  $lv->some_other_method  # same as $lv->get->some_other_method


DESCRIPTION

This class implements JavaScript lvalues (called ``Reference Types'' by the ECMAScript specification).


METHODS AND OVERLOADING

If a method is called that is not listed here, it will be passed to the property referenced by the lvalue. (See the last item in the SYNOPSIS, above.) For this reason, you should never call UNIVERSAL::can on a JE::LValue, but, rather, call it as a method ($lv->can(...)), unless you really know what you are doing.

Similarly, if you try to use an overloaded operator, it will be passed on to the object that the lvalue references, such that !$lvalue is the same as calling !$lvalue->get.

$lv = new JE::LValue $obj, $property
Creates an lvalue/reference with $obj as the base object and $property as the property name. If $obj is undefined or null, a TypeError is thrown. To create a lvalue that has no base object, and which will throw a ReferenceError when ->get is called and create a global property upon invocation of ->set, pass an unblessed reference to a global object as the first argument. (This is used by bare identifiers in JS expressions.)

$lv->get
Gets the value of the property.

$lv->set($value)
Sets the property to $value and returns $lv. If the lvalue has no base object, the global object will become its base object automatically. <Note:> Whether the lvalue object itself is modified in the latter case is not set in stone yet. (Currently it is modified, but that may change.)

$lv->call(@args)
If the property is a function, this calls the function with the base object as the 'this' value.

$lv->base
Returns the base object. If there isn't any, it returns undef or an empty list, depending on context.

$lv->property
Returns the property name.
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