restricting the number of instances of a character 1

[fluid11]

Newbie Perl question...

If you wanted to match for 2-5 x's, followed by a z, this pattern match should work...

/x{3,5}z/

If I enter less than 3 x's, it returns false as it should, but if I enter more than 5 x's, it returns true, which is wrong.

I'm using a script that tests different regular expressions...


print "Enter a string: ";
chomp($string = <STDIN>);
print &quot;Enter a pattern: &quot;;
chomp($pattern = <STDIN>);

if ($string =~ /$pattern/) { print &quot;True\n&quot;; }
else { print &quot;False\n&quot;; }



Also, the ? character is supposed to match zero or one instance of the character before it. If I enter ddd as the string, and /d?/ as the pattern, it still returns true. I thought that it would only return true if there were either zero or one instance of the letter d


Thanks,

ChrisP
RHCE, LPIC-1, CCNA, CNE, MCSE, +10 others

 

[chazoid]

In your first example, xxxxxxxxxxz would match because it does contain 5 x's followed by a z - xxxxx(xxxxxz)

/^x{2,5}z$/ should match what you want. ^ and $ anchor the match to the beginning and end of the string.

/d?/ will always return true.. any string could contain either zero d's or one d.

 

[fluid11]

I see, I need to anchor the pattern to search for that specific string.

Thanks,

ChrisP
RHCE, LPIC-1, CCNA, CNE, MCSE, +10 others