Re: regex matching exactly 10 digits

bugbear schreef:
Paul Lalli wrote:
[attribution removed by bugbear]:

#append 1 to 10 digit fax number
$fax_num =~ s/(\d{10,10})/1$1/;

You are missing the fact that a regexp doesn't care what *else* is in
the string. You are checking only to see if the string *contains*
the pattern. "At most" does not mean that the string cannot contain
more of that token. It means that this particular piece of the
regexp will not match more than that many. You need to explicitly
check that another digit neither precedes nor follows the ten that
you've found:

Depending on the OP's data, the simpler match
/^\d{10,10}$/
may serve.

echo 9876543210 | perl -wpe '
s/^(?=[0-9]{10}$)/x/
'
x9876543210

--
Affijn, Ruud

"Gewoon is een tijger."

.

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