The codeop module provides utilities upon which the Python read-eval-print loop can be emulated, as is done in the code module. As a result, you probably don’t want to use the module directly; if you want to include such a loop in your program you probably want to use the code module instead.
There are two parts to this job:
The codeop module provides a way of doing each of these things, and a way of doing them both.
To do just the former:
Tries to compile source, which should be a string of Python code and return a code object if source is valid Python code. In that case, the filename attribute of the code object will be filename, which defaults to '<input>'. Returns None if source is not valid Python code, but is a prefix of valid Python code.
It is possible (but not likely) that the parser stops parsing with a successful outcome before reaching the end of the source; in this case, trailing symbols may be ignored instead of causing an error. For example, a backslash followed by two newlines may be followed by arbitrary garbage. This will be fixed once the API for the parser is better.
Instances of this class have __call__() methods identical in signature to the built-in function compile(), but with the difference that if the instance compiles program text containing a __future__ statement, the instance ‘remembers’ and compiles all subsequent program texts with the statement in force.
Instances of this class have __call__() methods identical in signature to compile_command(); the difference is that if the instance compiles program text containing a __future__ statement, the instance ‘remembers’ and compiles all subsequent program texts with the statement in force.
A note on version compatibility: the Compile and CommandCompiler are new in Python 2.2. If you want to enable the future-tracking features of 2.2 but also retain compatibility with 2.1 and earlier versions of Python you can either write
try: from codeop import CommandCompiler compile_command = CommandCompiler() del CommandCompiler except ImportError: from codeop import compile_command
which is a low-impact change, but introduces possibly unwanted global state into your program, or you can write:
try: from codeop import CommandCompiler except ImportError: def CommandCompiler(): from codeop import compile_command return compile_command
and then call CommandCompiler every time you need a fresh compiler object.