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Steve,
No, I don't think it is worthwhile for speed reasons.
In AFL speed of execution of switch statement vs if-else is almost identical.
The only reason for using switch is that the code may look
"cleaner".
Best regards,
Tomasz Janeczko
amibroker.com
----- Original Message -----
From: "Steve Dugas" <sjdugas@xxxxxxxxxxx>
To: <amibroker@xxxxxxxxxxxxxxx>
Sent: Friday, May 25, 2007 5:26 PM
Subject: Re: [amibroker] Re: Nested Switch() statements
> Hi Tomasz - Do you thnk it is worthwhile ( maybe speed increase, for
> example? ) to convert existing if-else if-else if... over to Switch() ?
> Thank you!
>
> Steve
>
> ----- Original Message -----
> From: "Tomasz Janeczko" <groups@xxxxxxxxxxxxx>
> To: <amibroker@xxxxxxxxxxxxxxx>
> Sent: Friday, May 25, 2007 7:32 AM
> Subject: Re: [amibroker] Re: Nested Switch() statements
>
>
>> Hello,
>>
>> Frankly speaking fall-through is one of BEST features of switch()
>> statement.
>> I use it thousands of times. Implementations lacking that are missing
>> single most important thing in switch() statement.
>>
>> K&R "The C Programming Language" book is really recommended reading.
>>
>> Best regards,
>> Tomasz Janeczko
>> amibroker.com
>> ----- Original Message -----
>> From: "Nigel Rowe" <rho@xxxxxxxxxxxxxxx>
>> To: <amibroker@xxxxxxxxxxxxxxx>
>> Sent: Friday, May 25, 2007 12:12 PM
>> Subject: Re: [amibroker] Re: Nested Switch() statements
>>
>>
>>> On Fri, 25 May 2007, Ton Sieverding wrote:
>>>> Can you please explain me why 'switch statements are a frequent
>>>> source of bugs' ? If the last CASE is a DEFAULT then all possible
>>>> cases are covered. Or am I missing something in the AFL SWITCH
>>>> statement ?
>>>>
>>>> switch ( expression )
>>>> {
>>>> case constant-expression1 : statement;
>>>> case constant-expression2 : statement;
>>>> ...
>>>> case constant-expressionN : statement;
>>>>
>>>> default : statement;
>>>>
>>>> }
>>>>
>>>>
>>>> Ton.
>>>
>>> The 'standard' error when using a switch statement in 'C' and presumably
>>> AFL, is forgetting to put 'break;' statements in.
>>>
>>> To paraphrase your example (above) so it looks like this:-
>>>
>>> switch ( expression )
>>> {
>>> case constant-expression1 : statement1;
>>> case constant-expression2 : statement2;
>>> ...
>>> case constant-expressionN : statementN;
>>> default : statement_default;
>>> }
>>>
>>> If you leave out the break statements, and
>>> expression==constant_expression1 you will execute statement1 (what you
>>> wanted) AND ALSO statement2 AND ALSO statement3 AND ALSO ... statementN
>>> AND ALSO statement_default.
>>>
>>> It's sometimes called the 'fall-through' bug. It's easy to miss, can be
>>> a right pain!
>>>
>>>
>>> --
>>> Nigel Rowe
>>> rho \N{COMMERCIAL AT} swiftdsl \N{FULL STOP} com \N{FULL STOP} au
>>>
>>>
>>>
>>> Please note that this group is for discussion between users only.
>>>
>>> To get support from AmiBroker please send an e-mail directly to
>>> SUPPORT {at} amibroker.com
>>>
>>> For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
>>> http://www.amibroker.com/devlog/
>>>
>>> For other support material please check also:
>>> http://www.amibroker.com/support.html
>>>
>>> Yahoo! Groups Links
>>>
>>>
>>>
>>>
>>>
>>
>>
>> Please note that this group is for discussion between users only.
>>
>> To get support from AmiBroker please send an e-mail directly to
>> SUPPORT {at} amibroker.com
>>
>> For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
>> http://www.amibroker.com/devlog/
>>
>> For other support material please check also:
>> http://www.amibroker.com/support.html
>>
>> Yahoo! Groups Links
>>
>>
>>
>>
>
>
>
>
> Please note that this group is for discussion between users only.
>
> To get support from AmiBroker please send an e-mail directly to
> SUPPORT {at} amibroker.com
>
> For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
> http://www.amibroker.com/devlog/
>
> For other support material please check also:
> http://www.amibroker.com/support.html
>
> Yahoo! Groups Links
>
>
>
>
>
Please note that this group is for discussion between users only.
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SUPPORT {at} amibroker.com
For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG:
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