withhacks: building blocks for with-statement-related hackery

This module is a collection of useful building-blocks for hacking the Python “with” statement. It combines ideas from several neat with-statement hacks I found around the internet into a suite of re-usable components:

By subclassing the appropriate context managers from this module, you can easily do things such as:

skip execution of the code inside the with-statement

set local variables in the frame executing the with-statement

capture the bytecode from inside the with-statement

capture local variables defined inside the with-statement

Building on these basic tools, this module also provides some useful prebuilt hacks:

xargs: call a function with additional arguments defined in the body of the with-statement xkwargs: call a function with additional keyword arguments defined in the body of the with-statement namespace: direct all variable accesses and assignments to the attributes of a given object (like “with” in JavaScript or VB) keyspace: direct all variable accesses and assignments to the keys of of a given object (like namespace() but for dicts)

WithHacks makes extensive use of Noam Raphael’s fantastic “byteplay” module; since the official byteplay distribution doesn’t support Python 2.6, a local version with appropriate patches is included in this module.