Sven Barth ha scritto:
On 13.02.2013 10:11, Lukasz Sokol wrote:
On 13/02/2013 07:34, Michael Müller wrote:
I'm not sure if somebody else mentioned this already but I have the
feeling that Giuliano thinks that he has to decide to use try-finally
OR try-except but there are situations where you need both. One of
the criteria is if the object is local or global since for a global
object it is likely that you place the .Free (or for a global object
better FreeAndNil()) into a destructor or finalization section (which
means that you have to stop the program in case of an error and not
continue showing just a dialog) so you'll need only the try-except if
you want to catch the exception. In case of a local object you'll
ALWAYS have the lines
Obj := Class.Create;
try
// do some code
finally
Obj.Free;
end;
otherwise you'll end up with memory leaks.
If you want to catch the exception in this situation you'll put
try-except extra around try-finally so you'll end up with
Obj := Class.Create;
try
try
// do some code
finally
Obj.Free;
end;
except
writeln('We have a problem);
halt the program or reraise the exception or raise a new one
end;
Regards
To developers:
How would a generalized/packed construct like
try
[code block]
finally
[code block]
except
[code block]
end;
or what about
try
[code block]
except
[code block]
finally
[code block]
end;
Python provides the following:
try
[code block]
except
[code block]
else
[code block]
finally
[code block]
end;
which can be used in any reasonable combination: just try..except, just
try..finally just try..except..else etc.
The except..else is a very useful construct, because it provides a path
to a code block to execute only if there were no previous errors.
This wouldn't break any existing applications, just add very useful
features.
What fpc developers think about that?
Giuliano
--
Giuliano Colla
Before activating the tongue, make sure that the brain is connected
(anonymous)
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