Hoping this is the right place to post this, I would like to share a discovery which I have never heard of before. I have a directory containing a load of files which differ only in the number assigned to them e.g. file1.csv, file2.csv etc. etc.. There are usually more than 10 such files and I need them in numerical order not in the order; file1.csv, file10.csv, file11.csv etc. So I wrote a schwartztian transform to do the job and came up with this; 

@sorted = 
map {$_->[0]}
sort { $a->[1] <=> $b->[1] }
map { [$_, /^file(\d+)\.csv$/]}
@files;

[download]
What surprised me was that the regular expression actually returns $1, which is in this case an integer digit. So the RE is returning a scalar variable which is in fact what it matched and not the number of times it matched. Is this perl magic, does it happen because the RE is wrapped inside [] or have I missed a fundamental point somewhere? Or (at the risk of getting a big head) have I discovered something?

update (broquaint): title change (was Is this magic?)

In reply to Unexepected regex match return behaviour by readey

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