Two ways:

  1. make a copy of the string and weed out the space characters 
    my $string='i am using perl';
(my $str = $string) =~ s/\s+//g;

    [download]
    then match $pattern against $str
  2. insert \s* after (or before) every character in the pattern. 
    my $pattern = 'iamusingper';
$pattern =~ s/(.)/.\\s*$1/g;

    [download]
    then match $pattern against $string

Update: contrary to the title, you apparently don't want to ignore spaces in the regular expression (that's what the /x modifier is for), but in the string you are matching against.

2009-11-14
Original title: 'ignoring spaces in the (was: Regular expressions) string'

In reply to Re^3: Generalising string in pattern by shmem
in thread Generalising string in pattern by rajyalakshmi

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