[Tutor] exceptions
alan.gauld@bt.com
alan.gauld@bt.com
Mon, 15 Apr 2002 10:22:58 +0100
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> How do you approach error trapping and use exceptions in Python to
> take care of it? How do you for all the possible dumb user mistakes?
My tutor contains a page on this subject, plus we just had a thread on it.
> I mean give me the kind of thought process of how I should go about
> thinking this through in planning my program.
The main thing is just to think through what could
go wrong and catch those exceptions at the last point
that you can sensibly deal with them.
For production code I routinely put a try:/except/
handler around my entire program which just says
"Oops something unexpected happened". But thats just
to shield the gentle users from unsightly stack traces.
I comment it out during development/testing.
Alan g.
Author of the 'Learning to Program' web site
http://www.freenetpages.co.uk/hp/alan.gauld
<http://www.freenetpages.co.uk/hp/alan.gauld>
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<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002><FONT
face="Courier New" color=#0000ff>> </FONT></SPAN>How do you approach
error trapping and use exceptions in Python to <SPAN
class=700342009-15042002><FONT face="Courier New"
color=#0000ff> </FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002><FONT
face="Courier New" color=#0000ff>> </FONT> </SPAN>take care of it?
How do you for all the possible dumb user mistakes? <SPAN
class=700342009-15042002><FONT face="Courier New"
color=#0000ff> </FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN
class=700342009-15042002></SPAN></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002>My tutor
contains a page on this subject, plus we just had a thread on
it.</SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN
class=700342009-15042002></SPAN></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002>>
</SPAN>I mean give me the kind of thought process of how I should go
about <SPAN class=700342009-15042002><FONT face="Courier New"
color=#0000ff> </FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002><FONT
face="Courier New" color=#0000ff>> </FONT> </SPAN>thinking this through
in planning my program.<SPAN class=700342009-15042002><FONT face="Courier New"
color=#0000ff> </FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN
class=700342009-15042002></SPAN></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002><FONT
face="Courier New" color=#0000ff>The main thing is just to think through what
could </FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002><FONT
face="Courier New" color=#0000ff>go wrong</FONT> <FONT face="Courier New"
color=#0000ff>and catch those exceptions at the last point
</FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=700342009-15042002><FONT
face="Courier New" color=#0000ff>that you can sensibly deal with
them.</FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002></SPAN></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002>For production code I routinely put a try:/except/
</SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002>handler around my entire program which just says
</SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002>"Oops something unexpected happened". But thats just
</SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002>to shield the gentle users from unsightly stack traces.
</SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002>I comment it out during
development/testing.</SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002></SPAN></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT face="Courier New" color=#0000ff size=2><SPAN
class=700342009-15042002>
<P><FONT size=2>Alan g.<BR>Author of the 'Learning to Program' web site<BR><A
target=_blank
href="http://www.freenetpages.co.uk/hp/alan.gauld">http://www.freenetpages.co.uk/hp/alan.gauld</A></FONT>
</P></SPAN></FONT></FONT></DIV>
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