From: Andre Delfino Date: Wed, 22 Jul 2020 23:58:19 +0000 (-0300) Subject: Stick with the phrase "default parameter value" (GH-21590) X-Git-Tag: v3.10.0a1~355 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b9f6ac9d463b3c5823197b0bde3869876f65f413;p=thirdparty%2FPython%2Fcpython.git Stick with the phrase "default parameter value" (GH-21590) --- diff --git a/Doc/reference/compound_stmts.rst b/Doc/reference/compound_stmts.rst index c14e7c79fe14..df720f6cc323 100644 --- a/Doc/reference/compound_stmts.rst +++ b/Doc/reference/compound_stmts.rst @@ -571,9 +571,9 @@ value --- this is a syntactic restriction that is not expressed by the grammar. **Default parameter values are evaluated from left to right when the function definition is executed.** This means that the expression is evaluated once, when the function is defined, and that the same "pre-computed" value is used for each -call. This is especially important to understand when a default parameter is a +call. This is especially important to understand when a default parameter value is a mutable object, such as a list or a dictionary: if the function modifies the -object (e.g. by appending an item to a list), the default value is in effect +object (e.g. by appending an item to a list), the default parameter value is in effect modified. This is generally not what was intended. A way around this is to use ``None`` as the default, and explicitly test for it in the body of the function, e.g.::