use strict;
use warnings;


$_ = 'Page 1 of 5';

if(Page\&nbsp\;1\&nbsp\;of\&nbsp\;(/d+))
{
print "Number of Pages = ".$1;
}


__OUTPUT__
Backslash found where operator expected at test.pl line 9, near "Page\"
Backslash found where operator expected at test.pl line 9, near "&nbsp\"
        (Missing operator before \?)
Backslash found where operator expected at test.pl line 9, near "1\"
        (Missing operator before \?)
Backslash found where operator expected at test.pl line 9, near "&nbsp\"
        (Missing operator before \?)
Backslash found where operator expected at test.pl line 9, near "of\"
Backslash found where operator expected at test.pl line 9, near "&nbsp\"
        (Missing operator before \?)
syntax error at test.pl line 9, near "Page\"
Search pattern not terminated at test.pl line 9.

##</code><code>##

use strict;
use warnings;


$_ = 'Page&nbsp;1&nbsp;of&nbsp;5';

if(/Page\&nbsp\;1\&nbsp\;of\&nbsp\;(/d+)/)
{
print "Number of Pages = ".$1;
}

__OUTPUT__
Unmatched ( in regex; marked by <-- HERE in m/Page&nbsp;1&nbsp;of&nbsp;( <-- HER
E / at test.pl line 9.

##</code><code>##

use strict;
use warnings;


$_ = 'Page&nbsp;1&nbsp;of&nbsp;5';

if(/Page\&nbsp\;1\&nbsp\;of\&nbsp\;(\d+)/)
{
print "Number of Pages = ".$1;
}

__OUTPUT__
Number of Pages = 5

##</code><code>##

$string =~ m/regexp goes here/