[Tutor] finally

[Chris]

On 06/23/2010 10:59 PM, bob gailer wrote:
> On 6/23/2010 7:36 PM, Christopher King wrote:
>>     In a try except clause, you can end with finally block. I know it 
>> runs after the try and except blocks regardless of the outcome, but 
>> why use it. Couldn't you just put the code after the try and except 
>> block without using a finally block. Does the finally command do 
>> something I don't know about. Does it make your program more 
>> understandable in some way?
>
> Did you read the manual?
>
> "If finally <#finally> is present, it specifies a 'cleanup' handler. 
> The try <#try> clause is executed, including any except <#except> and 
> else <#else> clauses. If an exception occurs in any of the clauses and 
> is not handled, the exception is temporarily saved. The finally 
> <#finally> clause is executed. If there is a saved exception, it is 
> re-raised at the end of the finally <#finally> clause. If the finally 
> <#finally> clause raises another exception or executes a return 
> <simple_stmts.html#return> or break <simple_stmts.html#break> 
> statement, the saved exception is lost. The exception information is 
> not available to the program during execution of the finally 
> <#finally> clause.
>
> "When a return <simple_stmts.html#return>, break 
> <simple_stmts.html#break> or continue <simple_stmts.html#continue> 
> statement is executed in the try <#try> suite of a try 
> <#try>...finally <#finally> statement, the finally <#finally> clause 
> is also executed 'on the way out.' A continue 
> <simple_stmts.html#continue> statement is illegal in the finally 
> <#finally> clause. (The reason is a problem with the current 
> implementation --- this restriction may be lifted in the future)."
>
> -- 
> Bob Gailer
> 919-636-4239
> Chapel Hill NC
for the second quote, it means that the try...finally statement, finally 
will always execute even if you use return, break, or continue
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