>type 754047.pl
$value =~ s/\D//g;
$value =~ $1
if( $value =~ /(\d+)/ ){
  $value =~ $1
} else {
  undef $value;
}


>perl -c 754047.pl
syntax error at 754047.pl line 3, near "){"
754047.pl had compilation errors.

##</code><code>##

my $value = "abc456def";

$_ = $value;
$value = m/(\d+)/;

print "$value\n";   # Prints 1, not 456

##</code><code>##

my $value = "abc456def";

$_ = $value;
($value) = m/(\d+)/;

print "$value\n";   # Prints 456

##</code><code>##

my $value = "abc456def";

($value) = $value =~ m/(\d+)/;

print "$value\n";   # Prints 456