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Graham, of course, but that was not the point. I guess the example
wasn't clear.
What I tried to show is that, if you have large afl-files, with
#include etc., you need to watch out where/how you start "obviously
named" variables. Before you know it, you've already defined them
earlier in a different (global) context.
PS
--- In amibroker@xxxxxxxxxxxxxxx, Graham <kavemanperth@xxxx> wrote:
>
> why would you want to change the value of a variable, give them
> different names and save the headaches
>
> On 11/3/05, vlanschot <ecbu@xxxx> wrote:
> > Don't know whether this is helpful in clarifying it, but I'll
give it
> > a try:
> >
> > Say I have an AFL which looks like this:
> >
> > bla bla bla . . . . .
> >
> > examplevar=C/2; // This examplevar is now defined and thus
already by
> > definition a global variable !
> >
> > bla bla bla . . . .
> >
> > function Trial()
> > {
> > global examplevar; // Here I define examplevar again, but now as a
> > global variable within the function; this will cause a problem as
> > we'll see
> >
> > . . . .
> > anotherexamplevar=H/2;
> >
> > examplevar=C/3;
> >
> > return anotherexamplevar;
> > }
> >
> > . . . .
> >
> > CallTrial = Trial();
> >
> > CallExampleVar=examplevar;// This returns the value of the very
first
> > definition of examplevar, thus the one before = outside the
function.
> > It is therefore NOT equal to the "examplevar" defined as a global
> > variable within the function. In fact, there is no way to catch
this
> > latter value, unless you change the code/names/etc.
> >
> > This is my understanding and how I use it.
> >
> > PS
> >
> >
> >
> > --- In amibroker@xxxxxxxxxxxxxxx, "Ara Kaloustian" <ara1@xxxx>
wrote:
> > >
> > > Exactly ... That's how I use it ... but it is not working
reliably
> > >
> > > Ara
> > > ----- Original Message -----
> > > From: "Graham" <kavemanperth@xxxx>
> > > To: <amibroker@xxxxxxxxxxxxxxx>
> > > Sent: Wednesday, November 02, 2005 6:26 PM
> > > Subject: Re: [amibroker] Re: Global variables
> > >
> > >
> > > > If I want to use a variable that is defined within a function
or
> > > > procedure I first define it as a globla variable within the
> > function
> > > > or procedure. it is then available within the AFL after that
> > function
> > > > or procedure has been called
> > > >
> > > > On 11/3/05, Chuck <cstangor232@xxxx> wrote:
> > > > > According to the help manual, this is how global and local
> > variables
> > > relate
> > > > > to functions (depends on where they are first defined):
> > > > >
> > > > > If given identifier appears first INSIDE function
definition -
> > then it
> > > is
> > > > > treated as LOCAL variable.
> > > > > If given identifier appears first OUTSIDE function
definition -
> > then it
> > > is
> > > > > treated as GLOBAL variable.
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > From: "Ara Kaloustian" <ara1@xxxx>
> > > > > To: <amibroker@xxxxxxxxxxxxxxx>
> > > > > Sent: Wednesday, November 02, 2005 12:12 PM
> > > > > Subject: Re: [amibroker] Re: Global variables
> > > > >
> > > > >
> > > > > > Barry
> > > > > >
> > > > > > this is getting confusing ...
> > > > > >
> > > > > > Globals defined as such within a function seem available
> > globally ...
> > > but
> > > > > > as
> > > > > > I indicated earlier... not reliably.
> > > > > >
> > > > > > According to the help files, there is no distinction
between
> > globals
> > > > > > defined
> > > > > > within functions and variables initialized outside of
> > functions.
> > > > > >
> > > > > > Where did you see the distinction you mentioned?
> > > > > >
> > > > > > Hope this thread resolves the "mystery" of globals.
> > > > > >
> > > > > >
> > > > > > Ara
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > From: "Barry Scarborough" <razzbarry@xxxx>
> > > > > > To: <amibroker@xxxxxxxxxxxxxxx>
> > > > > > Sent: Wednesday, November 02, 2005 8:54 AM
> > > > > > Subject: [amibroker] Re: Global variables
> > > > > >
> > > > > >
> > > > > >> Global variables defined withing a function are scoped to
> > that
> > > > > >> function and all the sub functions within that function.
But
> > once
> > > > > >> you call outside that function the variable is not
> > available. If you
> > > > > >> want the variable to be global it has to be in a global
> > scope,
> > > > > >> outside of the functions that will use it. Declare it at
the
> > top of
> > > > > >> your code and it will have global scope as you mentioned.
> > Otherwise
> > > > > >> pass it as a parameter. This is much safer. You have to
be
> > careful
> > > > > >> when using globals because anyone can change a global
> > anytime and
> > > > > >> anywhere, darn hard to debug if that happens. If that is
OK
> > then
> > > > > >> make it global.
> > > > > >>
> > > > > >> I would have to look at your code to see what you are
doing.
> > > > > >>
> > > > > >> Barry
> > > > > >>
> > > > > >> --- In amibroker@xxxxxxxxxxxxxxx, "Ara Kaloustian"
> > <ara1@xxxx>
> > > > > >> wrote:
> > > > > >> >
> > > > > >> > I have had some problems with defining globals within a
> > function.
> > > > > >> >
> > > > > >> > Globals defined withing a function are not always
> > available to
> > > > > >> code later on. In one situation, a global defined within
a
> > prior
> > > > > >> function and used in an indicator, was not available to
some
> > copies
> > > > > >> of the indicator and was available to some others where
the
> > > > > >> indicator was used multiple times in same instance, but
on
> > different
> > > > > >> panes.
> > > > > >> >
> > > > > >> > If I initialize the variable at the beginning of the
> > program, it
> > > > > >> is automatically a global and always works reliably.
> > > > > >> >
> > > > > >> > Anyone with similar issues?
> > > > > >> >
> > > > > >> > Ara
> > > > > >> >
> > > > > >>
> > > > > >>
> > > > > >>
> > > > > >>
> > > > > >>
> > > > > >>
> > > > > >>
> > > > > >> 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 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 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 other support material please check also:
> > > > > http://www.amibroker.com/support.html
> > > > >
> > > > >
> > > > > Yahoo! Groups Links
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > > --
> > > > Cheers
> > > > Graham
> > > > AB-Write >< Professional AFL Writing Service
> > > > Yes, I write AFL code to your requirements
> > > > http://e-wire.net.au/~eb_kavan/ab_write.htm
> > > >
> > > >
> > > >
> > > > 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 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 other support material please check also:
> > http://www.amibroker.com/support.html
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
>
>
> --
> Cheers
> Graham
> AB-Write >< Professional AFL Writing Service
> Yes, I write AFL code to your requirements
> http://e-wire.net.au/~eb_kavan/ab_write.htm
>
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