Why doesn't my function execute when I use exec on a string? (the string is the name of the function)

Question

I have the following function in python:

def foo():
    print 1 
    return 1

In the shell, I run

foo()

and I get

1
1

as I should. But when I run the following in the shell

exec('foo')

I get nothing? why?

This is a diluted version of a much larger problem.

Martijn Pieters · Accepted Answer · 2013-07-22 00:16:40Z

1

You are only referencing the function name. Add parenthesis to actually call the function:

exec('foo()')

This will print 1; the return value is discarded as nothing captures it. You could add an extra print statement to show the return value:

exec('print foo()')

exec() does not mean 'execute the function named', it means 'execute the python code given'.

answered Jul 22, 2013 at 0:16

Martijn Pieters

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