Execute commands from file

[Steve Holden]

Martin Blume wrote:
> "Steve Holden" schrieb 
>>>> Try it on a file that reads something like
>>>>
>>>> xxx = 42
>>>> print xxx
>>>>
>>>> and you will see NameError raised because the assignment 
>>>> hasn't affected the environment for the print statement.
>>>>
>>> [...]
>>>
>> No, because there isn't one. Now try adding a function 
>> definition and see how well it works.
>>
> C:\temp>more question.py
> xxx=42
> print xxx
> def sowhat():
>         print xxx
> 
> print xxx
> 
> 
> C:\temp>c:\programme\python\python
> Python 2.4 (#60, Nov 30 2004, 11:49:19) 
>       [MSC v.1310 32 bit (Intel)] on win32
> Type "help", "copyright", "credits" or "license" 
>       for more information.
>>>> exec open("question.py").read()
> 42
> 42
>>>> sowhat()
> 42
>>>> xxx
> 42
> 
> 
> Seems to work great to me.
> 
> OTOH, this doesn't:
>>>> inp=open("question.py")
>>>> for l in inp:
> ...  exec l
> ...
> 42
> Traceback (most recent call last):
>   File "<stdin>", line 2, in ?
>   File "<string>", line 1
>     def sowhat():
>                 ^
> SyntaxError: unexpected EOF while parsing
> 
> 
> So it seems to depend on the way the file is read.
> 
It depends on the way the lines of the file are executed, not how they 
are read. And you may remember the original poster was proposing this:

inp = open(cmd_file)
 > for line in inp:
 >     exec line

As for your first example, why not just use execfile() ?

regards
  Steve
-- 
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