Execute python script inside a python script

Question

I have a scenario where i want to dynamically generate a python script - inside my main python script - store it as a string and then when need be, execute this dynamically generated script from my main script.

Is this possible, if so how?

thanks

Answer 1

May want to look at the statement exec: http://docs.python.org/release/2.5.2/ref/exec.html

Answer 2

Read up on the execfile() function.

http://docs.python.org/library/functions.html?highlight=exec#execfile

Answer 3

Not sure how wise this is but isn't the exec function what you use if you need to execute Python code?

Answer 4

If you want to execute the script within the context of the main script, you might want to check eval [ http://docs.python.org/py3k/library/functions.html#eval ]

Answer 5

For a script in a file use exec

For a script in a string use eval

!!! But !!!

before you use strings passed in from an external source, sanity check them! Otherwise you expose the ability to execute arbitrary code from within you program, so range check your variables!

You do not ever want to be asking the question:

"excuse me mam, did you really name your son Robert'); DROP TABLE students; -- "?

If you dont understand the reference - see this quick cartoon...

http://xkcd.com/327/

but when you EVAL - you are taking full responsibility for the instructions that you are eval'ing.

Answer 6

There is precedence for what you are trying to do. The collections.namedtuple function builds a template string which is passed to exec in order to build a dynamically defined class.