Of course the sprintf solution is completely sensible, but in the interest of TMTOWTDI and a little extra exposure for the poor underappreciated x operator, this will work too:
print "0" x (10-length($thing)) . $thing;

And yes, if length($thing) should happen to be larger than 10, the x treats the negative second operand as if it were zero.

In reply to Re: Adding Leading Zeros by seattlejohn
in thread Adding Leading Zeros by vanuatu10

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