Re: Determine first element in foreach

[neilwatson]

You can use a for loop instead of foreach

for ($i = 0; $i < $#mylist ; $i++) {
   say "first element" if ( $i == 0 );
}

[tobyink]

Even when you want to loop over the indexes, you can still use a foreach-style loop:

foreach my $i (0 .. $#mylist) {
   say "first element" if ( $i == 0 );
}

foreach-style loops are generally a better idea that C-style for loops. They're clearer; more declarative. It's harder to introduce an off-by-one error, and easier to spot a mistake.

[AnomalousMonk]

It's harder to introduce an off-by-one error, and easier to spot a mistake.

Indeed. Consider
    for ($i = 0; $i < $#mylist ; $i++) { ... }
in reply above:  $i < $#mylist vice  $i <= $#mylist — or did you have that in mind?

[tobyink]

I hadn't even noticed that! (Which is precisely my point.)