From 2647a3179be6573069b016befd46d42c234c9200 Mon Sep 17 00:00:00 2001 From: "Erlend E. Aasland" Date: Wed, 19 Jul 2023 00:46:50 +0200 Subject: [PATCH] Docs: Argument Clinic: Group guides about default values (python/cpython#106872) Previous ToC layout (excerpt): - How to use symbolic default values ... - How to assign default values to parameter - How to use the ``NULL`` default value - How to use expressions as default values New layout: - How to assign default values to parameter - The ``NULL`` default value - Symbolic default values - Expressions as default values --- Doc/howto/clinic.rst | 40 ++++++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 20 deletions(-) diff --git a/Doc/howto/clinic.rst b/Doc/howto/clinic.rst index 12d7a77d43..efeb22c618 100644 --- a/Doc/howto/clinic.rst +++ b/Doc/howto/clinic.rst @@ -564,22 +564,6 @@ How-to guides ============= -How to use symbolic default values ----------------------------------- - -The default value you provide for a parameter can't be any arbitrary -expression. Currently the following are explicitly supported: - -* Numeric constants (integer and float) -* String constants -* ``True``, ``False``, and ``None`` -* Simple symbolic constants like ``sys.maxsize``, which must - start with the name of the module - -(In the future, this may need to get even more elaborate, -to allow full expressions like ``CONSTANT - 1``.) - - How to to rename C functions and variables generated by Argument Clinic ----------------------------------------------------------------------- @@ -965,8 +949,8 @@ There's also special support for a default value of ``NULL``, and for simple expressions, documented in the following sections. -How to use the ``NULL`` default value -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +The ``NULL`` default value +^^^^^^^^^^^^^^^^^^^^^^^^^^ For string and object parameters, you can set them to ``None`` to indicate that there's no default. However, that means the C variable will be @@ -976,8 +960,24 @@ behaves like a default value of ``None``, but the C variable is initialized with ``NULL``. -How to use expressions as default values -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +Symbolic default values +^^^^^^^^^^^^^^^^^^^^^^^ + +The default value you provide for a parameter can't be any arbitrary +expression. Currently the following are explicitly supported: + +* Numeric constants (integer and float) +* String constants +* ``True``, ``False``, and ``None`` +* Simple symbolic constants like ``sys.maxsize``, which must + start with the name of the module + +(In the future, this may need to get even more elaborate, +to allow full expressions like ``CONSTANT - 1``.) + + +Expressions as default values +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The default value for a parameter can be more than just a literal value. It can be an entire expression, using math operators and looking up attributes