Hello list, The documentation states that the default value of function parameter, if mutable, can change it's default value at runtime due to be evaluated only once on function object creation. I would like to suggest the inclusion of an default language warning when this kind of construction is used, as it's Python specific behavior and can lead to "strange behavior" or misuse by programmers that are migrating from other languages to Python. This proposal was first open as a suggestion issue in bug track, but, as a request from Mr. Peterson, I'm rewriting it to this list. http://bugs.python.org/issue9646 Regards, -- .:''''':. .:' ` Sérgio Surkamp | Gerente de Rede :: ........ sergio@gruposinternet.com.br `:. .:' `:, ,.:' *Grupos Internet S.A.* `: :' R. Lauro Linhares, 2123 Torre B - Sala 201 : : Trindade - Florianópolis - SC :.' :: +55 48 3234-4109 : ' http://www.gruposinternet.com.br