Re: Bitwise Operator Error

[ikegami]

Strings used in numerical context as treated as decimal numbers. Use hex to convert them

Similarly, numerical literals are treated as decimal numbers. Prepend 0x.

#!/usr/bin/perl -w
# File displayPipeTracer2.pl

my $testString = "          00008008 000000FF 00800000";
$testString =~ s/\s+//g;

my $maskResult = hex($testString) & 0x400000000000000000000000;
print "Mask Result: $maskResult\n";

But those numbers are huge!

Integer overflow in hexadecimal number at script.pl line 7.
Hexadecimal number > 0xffffffff non-portable at script.pl line 7.
Integer overflow in hexadecimal number at script.pl line 7.
Hexadecimal number > 0xffffffff non-portable at script.pl line 7.
Mask Result: 4294967295

But Perl is capable of large number arithmetic using bigint/Math::BigInt.

#!/usr/bin/perl -w
# File displayPipeTracer2.pl

use bigint;

my $testString = "          00008008 000000FF 00800000";
$testString =~ s/\s+//g;
$testString = Math::BigInt->new("0x$testString");

my $maskResult = $testString & 0x400000000000000000000000;
print "Mask Result: $maskResult\n";

[ravishi]

Thanks, that worked. However, this is just a sample code. I tried using bigint in my main program and it gives me a whole slew of new errors. It is a GUI program using Tk and a few Tk modules (Tk::TableMatrix, Tk::Balloon, Tk::Bitmap, and Tk::Pane). I'm guessing that bigint and the Tk modules conflict. These are two separate errors I get when I run it with bigint. The second I get when I comment out the first error.

C:\code>DisplayPipeTracer15.pl -trace out.PipeTracer.xml
'8┬¿├⌐☻♥' isn't numeric at C:/Perl/site/
+lib/Tk/Widget.pm line 205.
 at C:\code\displayPipeTracer15.pl line 387

C:\code>DisplayPipeTracer15.pl -trace out.PipeTracer.xml
trace_file = out.PipeTracer.xml
Ports to be Analyzed: 1 2
'h┬Ñ├⌐☻♥' isn't numeric at C:/Perl/site/
+lib/Tk.pm line 250.
 at C:\code\displayPipeTracer15.pl line 159

Here is my code for the lines the errors point to. First is 387 and the second is 159.

Line 387:

    my $cycleAccept = $statusBar->Button(-text => "Go to", 
                                      -font => ['Arial', 8],
                                      -command=> \&GoToCycle, 
                                      -bd => 1, -takefocus => 'never',
                                      -highlightthickness => 0)->pack(
+-side => 'left');

Line 159:

        $PortFrame = $allPortsFrame->Scrolled('TableMatrix',
                                            -resizeborders=>'none',
                                            -titlerows => 1,
                                            -titlecols => 1,
                                            -background => 'white',
                                            -foreground => 'white',
                                            -borderwidth => 0,
                                            -rows => 6,
                                            -colstretchmode=>'all',
                                            -cols => 1,
                                            -colwidth => 25,
                                            -cache => 1,
                                            -scrollbars => "osoe")->pa
+ckAdjust(-side => "top", 
                                                                      
+         -fill => 'both', 
                                                                      
+         -expand => 1);

[ikegami]

bigint basically turns every number into an object which acts as a number. Limit the scope of bigint using curlies, or create the objects yourself were needed.

#!/usr/bin/perl -w
# File displayPipeTracer2.pl

{
   # Only makes objects from numbers in these curlies
   use bigint;

   my $testString = "          00008008 000000FF 00800000";
   $testString =~ s/\s+//g;
   $testString = Math::BigInt->new("0x$testString");

   my $maskResult = $testString & 0x400000000000000000000000;
   print "Mask Result: $maskResult\n";
}

#!/usr/bin/perl -w
# File displayPipeTracer2.pl

my $testString = "          00008008 000000FF 00800000";
$testString =~ s/\s+//g;
$testString = Math::BigInt->new("0x$testString");

my $mask = Math::BigInt->new('0x400000000000000000000000');

my $maskResult = $testString & $mask;
print "Mask Result: $maskResult\n";