Re: Hex Question(s)

Prepend '0x' to the string and it will maintain its numeric value.

#!/usr/bin/perl

  use strict;
  no warnings 'numeric';

  my $this = sprintf("0x%x", 40);
  my $that = sprintf("0x%x", 2);

  my $other = $this + $that;

  printf "$other %x\n", $other;

__END__
42 2a
[download]

Update: Added no warnings for the -w happy...

Update: This is perl, v5.6.0 built for i386-linux

Comment on Re: Hex Question(s) Download Code

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Re^2: Hex Question(s) by Corion (Patriarch) on Mar 27, 2008 at 16:36 UTC
I guess you didn't try your program: `C:\>perl -w 676783.pl Argument "0x2" isn't numeric in addition (+) at 676783.pl line 8. Argument "0x28" isn't numeric in addition (+) at 676783.pl line 8. 0 0` [download] This oneliner shows that this isn't the case: `>perl -le "print '0x42' + '0x10'" 0` [download] But of course, if you leave off the single quotes, Perl will interpret the numbers as numbers (in hexadecimal notation) and add them like it does add all numbers (regardless of their notation): `>perl -le "print 0x42 + 0x10" 82` [download] ... but that's because internally, Perl does just see the numbers as numbers (without any representation to any base).	[reply] [d/l] [select]
Re^2: Hex Question(s) by TGI (Parson) on Mar 27, 2008 at 16:51 UTC
What version of Perl are you using? When I run your code on my system (WinXP, ActivePerl 5.8.8), I get an incorrect answer. I added a the `use warnings` pragma to your code and got this result: `C:\> test.pl Argument "0x2" isn't numeric in addition (+) at C:\test.pl line 9. Argument "0x28" isn't numeric in addition (+) at C:\test.pl line 9. 0 0` [download] You can specify hexadecimals in literal code by appending an '0x' to the value. I suppose, if you really wanted to get to a hexadecimal from a string, you could use string eval. `my $this = sprintf("0x%x", 40); my $that = sprintf("0x%x", 2); my $other = eval "$this + $that"; printf "$other %x\n", $other;` [download] I'd be inclined to go with hex, though. TGI says moo	[reply] [d/l] [select]
Re^2: Hex Question(s) by deadlock (Initiate) on Mar 27, 2008 at 16:38 UTC
`perl -w test.pl Argument "0x2" isn't numeric in addition (+) at test.pl line 7. Argument "0x28" isn't numeric in addition (+) at test.pl line 7. 0 0` [download]	[reply] [d/l]

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