Hello,
This is new feature introduced in one of recent BETAs
and
not available in "official" guide.
It is however described
here:
http://www.amibroker.com/guide/v50/keyword/switch.html
Best
regards,
Tomasz Janeczko
amibroker.com
----- Original Message -----
From: "t_ohrt" <to56@xxxxxxxxx>
To: <amibroker@xxxxxxxxxps.com>
Sent:
Friday, May 25, 2007 6:23 PM
Subject: [amibroker] Re: Nested Switch()
statements
Interesting topic, but where in the Amibroker user´s guide
can I find
information covering the Switch()
function?
T.O.
--- In amibroker@xxxxxxxxxps.com,
"Tomasz Janeczko" <groups@xxx>
wrote:
>
>
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@xxx>
> To: <amibroker@xxxxxxxxxps.com>
>
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@xxx>
>
> To: <amibroker@xxxxxxxxxps.com>
>
> 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@xxx>
> >> To: <amibroker@xxxxxxxxxps.com>
>
>> 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-_expression_1 : statement;
> >>>> case
constant-_expression_2 : statement;
> >>>> ...
>
>>>> case constant-_expression_N : 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-_expression_1 : statement1;
> >>> case
constant-_expression_2 : statement2;
> >>> ...
>
>>> case constant-_expression_N : 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.
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