in reply to Re^2: Generalising string in pattern
in thread Generalising string in pattern

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;

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

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    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'

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Re^4: Generalising string in pattern
by keszler (Priest) on Nov 13, 2009 at 15:27 UTC
    An alternate to option 2, slightly faster: 
    use strict;
use Benchmark qw/cmpthese/;
my $p = 'stringwithnospacesinit';
my ($a,$b);
cmpthese(
  -5,
  {
    a => sub{
      $a = $p;
      $a =~ s/(.)/$1\\s*/g;
    },
    b => sub{
      $b = $p;
      $b = join('\s*',split(//,$b));
    },
  }
);
__END__
     Rate    a    b
a 62530/s   -- -20%
b 78403/s  25%   --

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    update - typo fix
[reply]
[d/l]

      ... and add a leading and/or trailing \s* ;-)

      (update: only needed if the pattern is anchored)

[reply]
[d/l]

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