Right, I better set $GetLocation = -1, but, what I am looking for
is if there is something working like grep does ?
@elemLoc = grepIndex (/pattern/, @list); # something like that ?
And is that I can't aviod to use loop to search for matching ?
Rgds,
Connie
----- Original Message -----
From: "Jeff 'japhy' Pinyan" <[EMAIL PROTECTED]>
To: "Connie Chan" <[EMAIL PROTECTED]>
Cc: <[EMAIL PROTECTED]>
Sent: Saturday, July 13, 2002 4:54 AM
Subject: Re: How can I get element location in array ?
> On Jul 13, Connie Chan said:
>
> >I now have an array like this : @list = ('1234', '4567', '789A', 'BCDE',
> >'FGHI', .....);
> >
> >and now, I want to find where is the location of 'BCDE' in list , so I
> >write like this :
> >
> >my @list = ('1234', '4567', '789A', 'BCDE', 'FGHI');
> >my $GetLocation = 0;
> >my $value = 'BCDE';
> >
> >for (my $atLoc = 0; $atLoc <= $#list and ! $GetLocation ; $atLoc++)
> >{ $GetLocation = $atLoc if ($value eq $list[$atLoc]) }
> >
> >ok, so $GetLocation is the result I want...
> >but any other smarter method ?
>
> Once you have FOUND the element, you can exit the loop. Also, your loop
> is testing !$GetLocation, which returns true if the element is found at
> index 0. Your code will end up ASSUMING the element is index 0 if it
> isn't found in the array at all. Here's are two solutions:
>
> my @list = ...;
> my $wanted = 'foo';
> my $pos = -1; # -1 means not found
>
> for (my $i = 0; $i < @list; $i++) {
> $pos = $i, last if $list[$i] eq $wanted;
> }
>
> Now you'll have $pos being either -1 (not found) or the index in the
> array. You'd check via
>
> if ($pos != -1) { ... } # it was found
> else { ... } # it wasn't found
>
> Here's the other solution:
>
> my @list = ...;
> my $wanted = 'foo';
> my $pos = 0; # 0 means not found
>
> for (my $i = "0E0"; $i < @list; $i++) {
> $pos = $i, last if $list[$i] eq $wanted;
> }
>
> Now you'll have $pos being either 0 (not found), or the index in the
> array, BUT! it will be "0E0" if it was the first element. This means you
> CAN test it like so:
>
> if ($pos) { ... } # it was found
> else { ... } # it wasn't found
>
> because "0E0" is a string that is not false, but is treated as the number
> 0 when used numerically.
>
> --
> Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/
> RPI Acacia brother #734 http://www.perlmonks.org/ http://www.cpan.org/
> ** Look for "Regular Expressions in Perl" published by Manning, in 2002 **
> <stu> what does y/// stand for? <tenderpuss> why, yansliterate of course.
> [ I'm looking for programming work. If you like my work, let me know. ]
>
>
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