Hello! I've started learning Perl this weekend (read Learning Perl and am making my way through Intermediate Perl now), and was quite drawn in by what seems to be a very strong community. The concept of this site makes me warm and fuzzy :)

I'd like to learn Perl in "the Perl way," as I know such styles exist for a reason and help to improve readability among other programmers of the language. So comments about style in addition to actual functionality would be appreciated.

I have a general question, involving the optional nature of parentheses, and an example of said question has arisen in this little exercise from the book that I'm doing.
"Write a program that takes a list of filenames on the command line and uses grep to select the ones whose size in bytes is less than 1000. Use map to transform the strings in this list, putting four space characters in front of each and a newline character after. Print the resulting list." (I increased the number to 10000 to easier accommodate files I had sitting on my desktop for testing purposes.)
Here's what I have:
use warnings;
use strict;

my @small_files = grep( (-s) < 10000, @ARGV);
my @output = map s/(.*)/    $1\n/, @small_files;
print @output;

[download]

First question is, of course: my isn't it working like I want? The grep seems to be fine, but the @output seems to contain 4 1's instead of 4 modified strings of filenames.
Second question: when I first wrote it, my grep statement looked like: my @small_files = grep -s < 10000, @ARGV;
But that had an error, so I had to put the parentheses in, which made me kinda sad. Why was that the case?
Thanks!
~J. (Just Another Perl Newbie?)

In reply to Newbie: parentheses, map, etc. by nefigah

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