.. _use-dict-literal:

use-dict-literal / R1735
========================

**Message emitted:**

``Consider using '%s' instead of a call to 'dict'.``

**Description:**

*Emitted when using dict() to create a dictionary instead of a literal '{ ... }'. The literal is faster as it avoids an additional function call.*

**Problematic code:**

``empty_dict.py``:

.. literalinclude:: /data/messages/u/use-dict-literal/bad/empty_dict.py
    :language: python


``init_dict_from_another.py``:

.. literalinclude:: /data/messages/u/use-dict-literal/bad/init_dict_from_another.py
    :language: python


``init_with_keyword.py``:

.. literalinclude:: /data/messages/u/use-dict-literal/bad/init_with_keyword.py
    :language: python


**Correct code:**

``empty_dict.py``:

.. literalinclude:: /data/messages/u/use-dict-literal/good/empty_dict.py
    :language: python


``init_dict_from_another.py``:

.. literalinclude:: /data/messages/u/use-dict-literal/good/init_dict_from_another.py
    :language: python


``init_with_litteral.py``:

.. literalinclude:: /data/messages/u/use-dict-literal/good/init_with_litteral.py
    :language: python



**Additional details:**

https://gist.github.com/hofrob/ad143aaa84c096f42489c2520a3875f9

This example script shows an 18% increase in performance when using a literal over the
constructor in python version 3.10.6.

**Related links:**

- `Performance Analysis of Python’s dict() vs dict literal <https://madebyme.today/blog/python-dict-vs-curly-brackets/>`_


Created by the `refactoring <https://github.com/pylint-dev/pylint/blob/main/pylint/checkers/refactoring/refactoring_checker.py>`__ checker.