Thanks! That’s exactly what I’m looking for. I’m going to update the post with a second version taken from the comments. It will definitely be more “perly.”

- Scope your variables with ‘my’

$n = <STDIN> # $n here will be global which could end up being messy
my $n = <STDIN> # $n here is lexical – it falls out of scope at the end of the sub

- Use chomp() instead of chop(). chop() removes the last character from a string regardless of what the character is; chomp() only removes the last character if it’s a newline. This is a nice piece of idiot-proofing for those times when you’re absolutely 100% positive your string ends with a newline, but you are nonetheless wrong

- Don’t use the & when calling a sub (unless you understand what the & does) – just include the parens at the end so the parser understands you’re making a sub call. Older Perl books/tutorials generally included the & on the front of a sub call, but it’s not necessary and can break things in ways you’re not expecting if you don’t do lots of Perl.

&fibonacci(5); # Generally considered bad, though it works and hurts nothing in your example
fibonacci(5); # works just fine, regardless of where you defined the sub
fibonacci(); # if your sub didn’t require any args, you just include empty parens

- The variables $a and $b are used by the builtin function sort(). You aren’t using sort() in your code, so in this case your $a and $b variables aren’t going to hurt anything, but it’s generally a good idea to get in the habit of staying away from those particular variable names – use $x and $y or whatever instead. If your code or any external code (a module or library) that you might be using uses sort anywhere and your code includes $a and $b, you can occasionally get hard-to-track-down bugs.

- In Perl, you can swap two variables’ values without using a temporary variable like so:

$a = ‘one’;
$b = ‘two’;
($a, $b) = ($b, $a);
print “$a — $b”; # ‘two — one’

- Last, your main sub isn’t necessary. Any code that isn’t wrapped in a sub becomes your program’s mainline. The little example below will run the first two lines of code even though they aren’t in a specifically named and called sub.

#################
my $var = mysub();
print “$var\n”;

sub mysub {
return ‘hi there’;
}
#################

- OK – putting it all together we get this:

#!/usr/bin/perl

print “How many numbers of the sequence would you like? “;
chomp( my $n = <STDIN> );
print “\n”; # Just to visually separate the user’s input from the program’s output
fibonacci($n);

sub fibonacci {
my $a = 0;
my $b = 1;
for( 0 .. ($_[0] – 1) ) {
print “$a\n”;
($a, $b) = ($b, ($a + $b));
}
}

I really like what you’re doing here and think it’s a great idea, but you do use practically the same code everywhere. I’d like to see more language specific construct, for example, it’s not common to write
for ($i=0;$i lt $n; $i++)
but instead:
for(0…$n-1)
also, i think printf isn’t used as commen as normal print, you can just write
print “$a\n”; , variables get substituted in”‘s just like in php.

also: how about some golf:

++$b;for(0..lt>-1){print”$a\n”;($b)=($s,$a)=($a+$b,$b);}

works just as well (remember to replace the “lt”