I have a directory with the following files: 
 
 1.1.1.txt
 1.1.txt
 1.txt
 2.txt
 3.txt

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My objective is to print off only the files with names of the format nnnnn.txt where n is a number. This prints too many: 
perl -e "print grep {/\d+\.txt/} glob('*.txt');"
1.1.1.txt1.1.txt1.txt2.txt3.txt

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I suspect the problem lies with the regex. The original grep is looking for n.txt, so we'll make $s textural: 
perl -e "$s=qq(1.1.1); if ($s=~/\d+/) {print 'it is a number'};"
it is a number

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But it isn't a 'number'. I still want to be able to match files with the type 200000.txt at some point. I thought this problem had to do with greediness, so I tried this: 
perl -e "$s=qq(1.1.1); if ($s=~/\d+?/) {print 'it is a number'};"
it is a number

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To no avail. What is the correct regex and why didn't this work?

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In reply to regex matching number by InfiniteSilence

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