Perl: Where am I in a foreach loop?

jrtayloriv · 01-30-2005, 10:49 AM

Is there a way that I can make a reference to the number of the array member(if foreach loop is on $array[1] - the number 1 is what I'm looking for) that I am at in a foreach loop? For instance how can I say:

foreach (@array)
{
if (NUMBER_OF_ARRAY_MEMBER_I'M_ON_NOW>2)
{
do some stuff;
}
}

Yeah, I know it's an ugly example

, but I don't know any terminology that would enable me to word it more clearly. And yes, I also realize I could use a regular for loop to do such a thing quite easily, but I am just curious....

Thanks,
jrtayloriv

mas00d · 01-30-2005, 11:01 AM

hi,
As i m new to perl i dont know the best way but i would prefer doing this:

$i=0;
foreach (@array)
{
if ($i > 2)
{
do some stuff;
}
$i=$i +1;
}

david_ross · 01-30-2005, 11:06 AM

What about this:

Code:

#!/usr/bin/perl

$arr[0]="zero";
$arr[1]="one";
$arr[2]="two";
$arr[3]="three";
$arr[4]="four";
$arr[5]="five";

for($num=0;$num<@arr;$num++){
 if($num>2){print "*"}
 else{print " "}
 print " $num $arr[$num]\n";
}

exit;

jrtayloriv · 01-30-2005, 10:43 PM

Not exactly what I was looking for - my fault for wording the question poorly. I found the answer in the Camel:

Quote:

There is no way with foreach to tell where you are in a loop. You may compare adjacent elements, by remembering the previous one in a variable, but sometimes you just have to break down and write a three-part for loop with subscripts. That's what the other kind of for loop is there for, after all.

---Section 4.4.3 [Programming Perl]

jrtayloriv