Likewise. for(;;) is a dirty C trick that doesnt really belong in perl. Especially when the replacement is easier to understand, less prone to error and most importantly more efficient.

y @temps =  ('69', '70', '71');
my @numbers = ('0.115', '3.667', '4.78');
my $highNumberIndex = 0;

for my $i (0..$#number)
{
  if ($numbers[$highNumberIndex] < $numbers[$i])
  {
    $highNumberIndex = $i;
  }
}
print $temps[$highNumberIndex];
[download]

--- demerphq
my friends call me, usually because I'm late....

Likewise. for(;;) is a dirty C trick that doesnt really belong in perl. Especially when the replacement is easier to understand, less prone to error and most importantly more efficient.

Oh, really? A significant part of Perl comes from C, shell, AWK, Ada, BASIC, Python, Fortran, and other languages. Why is for (;;) a dirty C trick that doesn't really belong in Perl, and why isn't for $var (@array) a dirty AWK trick that doesn't belong in Perl? Leave it to the villains of "Harry Potter and the Secret Chamber" to strive for "pure blood".

I also disagree with your other claims. I'm not convinced that the replacement is easier to understand, less prone to error, and more efficient. Let's consider the "dirty C trick":

    for (my $i = 0; $i < 1000000; $i += 2) {$sum += $i}
[download]

The AWK-like replacement would be:

    for my $i (map {$_ * 2} 0 .. 1000000 / 2) {$sum += $i}
[download]

I don't think that's easier to understand, or less prone to error. As for efficientcy:

#!/usr/bin/perl

use strict;
use warnings;

use Benchmark;

timethese -10, {
    C    =>  'my $sum; for (my $i = 0; $i < 1000000; $i += 2) {$sum +=
+ $i}',
    AWK  =>  'my $sum; for my $i (map {$_ * 2} 0 .. 1000000 / 2) {$sum
+ += $i}'
};

__END__
Benchmark: running C, AWK for at least 10 CPU seconds...
     C: 10 wallclock secs (10.66 usr +  0.00 sys = 10.66 CPU) @  1.41/
+s (n=15)
   AWK: 10 wallclock secs (10.08 usr +  0.00 sys = 10.08 CPU) @  0.69/
+s (n=7)
[download]

Abigail

Abigail,

That was an off the cuff remark about using for(;;) instead of for ($lower..$upper). Of course there are uses of for(;;) that do not map on to for ($i..$j). However this wasnt one of them. And for this type of case I stand by my remarks.

Furthermore comparing

for (my $i = 0; $i < 1000000; $i += 2) {$sum += $i}
[download]

to

for my $i (map {$_ * 2} 0 .. 1000000 / 2) {$sum += $i}
[download]

is a bit strange, when internally it is closer to

{
 my $i=0;
 while ($i < 1000000) {
    $sum+=$i;
 } continue {
    $i+=2;
 }
}
[download]

As for all the other languages you listed, none (that I know of) but the C derivatives have this weird form of while loop pretending to be a for loop. For a programmer whose experience is limited to one of the ones without the equivelence the construct is particularly confusing. So from that POV I stand by calling the three arg for loop construct a dirty C trick.

And I stand by the efficiency claims for the case to which I was primarily referring:

use strict;
use Benchmark qw(cmpthese);
our $sum;

cmpthese -10,{ 'foreach' => <<'CODE', 'for(;;)' => <<'MORECODE' };
$::sum=0;
for my $i (0..10_000) { $::sum+=$i; }
CODE
$::sum=0;
for (my $i=0;$i<10_000;$i++) { $::sum+=$i; }
MORECODE

__END__
Benchmark: running for(;;), foreach, each for at least 10 CPU seconds.
+..
   for(;;): 11 wallclock secs (10.61 usr +  0.00 sys = 10.61 CPU) @ 85
+.30/s (n=905)
   foreach: 11 wallclock secs (10.63 usr +  0.00 sys = 10.63 CPU) @ 14
+3.15/s (n=1521)
          Rate for(;;) foreach
for(;;) 85.3/s      --    -40%
foreach  143/s     68%      --
[download]

Id say thats more efficient wouldnt you?

--- demerphq
my friends call me, usually because I'm late....