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ClosureExpression
===================================================================

.. currentmodule:: gi.repository.Gtk





.. class:: ClosureExpression(*args, **kwargs)
   :no-contents-entry:


Superclasses: :class:`~gi.repository.Gtk.Expression`





An expression using a custom ``GClosure`` to compute the value from
its parameters.



Constructors
------------

.. rst-class:: interim-class

.. class:: ClosureExpression
   :no-index:


   .. classmethod:: new(value_type: type, closure: ~typing.Callable[[...], ~typing.Any], params: ~typing.Sequence[~gi.repository.Gtk.Expression] | None = None) -> ~gi.repository.Gtk.ClosureExpression

      Creates a ``GtkExpression`` that calls ``closure`` when it is evaluated.

      ``closure`` is called with the ``this`` object and the results of evaluating
      the ``params`` expressions.







      :param value_type: the type of the value that this expression evaluates to


      :param closure: closure to call when evaluating this expression. If closure is floating, it is adopted


      :param params: expressions for each parameter