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| -rw-r--r-- | Doc/ref/ref4.tex | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/Doc/ref/ref4.tex b/Doc/ref/ref4.tex index dcdc823..12a2b92 100644 --- a/Doc/ref/ref4.tex +++ b/Doc/ref/ref4.tex @@ -97,10 +97,20 @@ searched. The global statement must precede all uses of the name. The built-in namespace associated with the execution of a code block is actually found by looking up the name \code{__builtins__} in its global namespace; this should be a dictionary or a module (in the -latter case the module's dictionary is used). Normally, the -\code{__builtins__} namespace is the dictionary of the built-in module -\module{__builtin__} (note: no `s'). If it isn't, restricted -execution\indexii{restricted}{execution} mode is in effect. +latter case the module's dictionary is used). By default, when in the +\module{__main__} module, \code{__builtins__} is the built-in module +\module{__builtin__} (note: no `s'); when in any other module, +\code{__builtins__} is an alias for the dictionary of the +\module{__builtin__} module itself. \code{__builtins__} can be set +to a user-created dictionary to create a weak form of restricted +execution\indexii{restricted}{execution}. + +\begin{notice} + Users should not touch \code{__builtins__}; it is strictly an + implementation detail. Users wanting to override values in the + built-in namespace should \keyword{import} the \module{__builtin__} + (no `s') module and modify its attributes appropriately. +\end{notice} The namespace for a module is automatically created the first time a module is imported. The main module for a script is always called |