Thanks Paul!
"Gowers, Paul
(CRTLDN)" To: 'Philip Morley'
<[EMAIL PROTECTED]>
<Paul.Gowers@co cc:
ncert.com> Subject: RE: Pattern matching null
strings
29/04/02 15:16
Phil
Try this:
print "Please enter the string: ";
$Response = <STDIN>;
chomp $Response;
if ($Response !~ /^\w+$/) {
warn "Error - string not valid.\n";
}
The regexp is looking for one or more word characters between the start and
end of the value held in $Response. This disallows an empty string as well
as any value containing whitespace, punctuation etc. If you wanted to be
more specific, you could use a character class instead of \w (eg [A-Za-z]
to allow only alphabetic characters).
Cheers
Paul
-----Original Message-----
From: Philip Morley [mailto:[EMAIL PROTECTED]]
Sent: 29 April 2002 15:05
To: [EMAIL PROTECTED]
Subject: Pattern matching null strings
Hi,
Can someone show me a more elegant way of validating user input than this:
print "Please enter the string: ";
$Response = <STDIN>;
chomp $Response;
if (($Response =~ /\W/) || ($Response eq "")) {
warn "Error - string not valid.\n";
}
Basically I want the $Response to be only a word character and not null
(i.e. warn if the user just presses return). Is there a pattern match I
can use so that I don't have to explicitly check if eq ""?
Thanks in advance,
Phil Morley
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