"Breaking" the __main_

vsoler

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Mar 14, 2010, 7:34:53 AM3/14/10

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Hello,

I am still learning python, thus developnig small scripts.

Some of them consist only of the main module. While testing them
(debugging) I sometimes want to stop the script at a certain point,
with something like stop, break, end or something similar.

What statement can I use?

Vicente Soler

Mark Lawrence

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Mar 14, 2010, 7:53:22 AM3/14/10

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Something like
import sys
sys.exit()?

HTH.

Mark Lawrence

Michael Rudolf

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Mar 14, 2010, 8:20:03 AM3/14/10

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Am 14.03.2010 12:53, schrieb Mark Lawrence:

> vsoler wrote:
>> I sometimes want to stop the script at a certain point,
>> with something like stop, break, end or something similar.
>> What statement can I use?

> Something like
> import sys
> sys.exit()?

Or just "raise SystemExit", "raise SyntaxError" or any other Exception.
But you won't have to: If you use IDLE, you can just set breakpoints in
your code: enable the debugger in debug-debugger and set breakpoints via
right click in your source file.

Or you could use a real debugger, like pdb
http://docs.python.org/library/pdb.html

HTH,
Michael

Steve Holden

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Mar 14, 2010, 9:07:21 AM3/14/10

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Mark Lawrence wrote:

> Something like
> import sys
> sys.exit()?
>

> HTH.

I think it's less than likely that it will help, since once sys.exit()
is called the program is no longer available for inspection.

The OP is probably looking for the "pdb" module in the standard library.
The documentation is good enough to get you started.

regards
Steve
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Joaquin Abian

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Mar 14, 2010, 10:03:29 AM3/14/10

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Hola Vicente,

You need a debugger.
A practical solution to start with is to use an IDE with an integrated
debugger.
Stani's Python Editor (SPE) is a lightweight IDE with pdb integrated
(with style checker also).
It is a very good ide for learning (simple and not cluttered) but also
for medium size
applications (it is very well designed).

atb

Joaquin

pyt...@bdurham.com

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Mar 14, 2010, 11:03:47 AM3/14/10

to Michael Rudolf, pytho...@python.org

Michael,

> Or you could use a real debugger, like pdb
> http://docs.python.org/library/pdb.html

Any reason you prefer PDB over WinPDB?
http://winpdb.org/

Thanks,
Malcolm

Tim Chase

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Mar 14, 2010, 2:30:59 PM3/14/10

to pyt...@bdurham.com, pytho...@python.org, Michael Rudolf

pyt...@bdurham.com wrote:
>> Or you could use a real debugger, like pdb
>> http://docs.python.org/library/pdb.html
>

> Any reason you prefer PDB over WinPDB?
> http://winpdb.org/

I always count "in the standard library" as a big plus over any
add-ons It's nice to know about alternatives such as WinPDB, but
everybody that has python also has pdb already installed.

-tkc