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.. rst-class:: align-right

**built-in method**

.. index:: pair: findall/3; Built-in method
.. _methods_findall_3:

``findall/3``
=============

Description
-----------

::

   findall(Template, Goal, List)

Collects a list of solutions for the goal. The order of the elements in
the list follows the order of the goal solutions. It succeeds returning
an empty list when the goal has no solutions.

This built-in meta-predicate is declared as a private method and thus
cannot be used as a message to an object.

Meta-predicate template
-----------------------

::

   findall(*, 0, *)

Modes and number of proofs
--------------------------

::

   findall(?term, +callable, ?list) - zero_or_one

Errors
------

| ``Goal`` is a variable:
|     ``instantiation_error``
| ``Goal`` is neither a variable nor a callable term:
|     ``type_error(callable, Goal)``
| ``Goal`` is a call to a non-existing predicate:
|     ``existence_error(procedure, Predicate)``

Examples
--------

| To find all solutions in the context of the object or category containing the call:
|     ``findall(Template, Goal, List)``
| To find all solutions of sending a message to :term:`self`:
|     ``findall(Template, ::Message, List)``
| To find all solutions of sending a message to an explicit object:
|     ``findall(Template, Object::Message, List)``

.. seealso::

   :ref:`methods_bagof_3`,
   :ref:`methods_findall_4`,
   :ref:`methods_forall_2`,
   :ref:`methods_setof_3`
