Generate .pyc from Python AST?


How would I generate a .pyc file from a Python AST such that I could import the file from Python?

I’ve used compile to create a code object, then written the co_code attribute to a file, but when I try to import the file from Python, I get an ImportError: Bad magic number in output.pyc.

Asked By: exupero



The compile standard function provides this function for both Python 2.x and Python 3.x. However, you will find that the AST representation between 2.x and 3.x is quite different, so be prepared for that.

Answered By: Greg Hewgill

The solution can be adapted from the py_compile module:

import marshal
import py_compile
import time
import ast

codeobject = compile(ast.parse('print "Hello World"'), '<string>', 'exec')

with open('output.pyc', 'wb') as fc:
    py_compile.wr_long(fc, long(time.time()))
    marshal.dump(codeobject, fc)
    fc.flush(), 0)

Answered By: exupero