lib/perl5/5.8.8/Math/BigFloat/Trace.pm

   1 #!/usr/bin/perl -w
   2
   3 package Math::BigFloat::Trace;
   4
   5 require 5.005_02;
   6 use strict;
   7
   8 use Exporter;
   9 use Math::BigFloat;
  10 use vars qw($VERSION @ISA $PACKAGE @EXPORT_OK
  11             $accuracy $precision $round_mode $div_scale);
  12
  13 @ISA = qw(Exporter Math::BigFloat);
  14
  15 $VERSION = 0.01;
  16
  17 use overload;   # inherit overload from BigFloat
  18
  19 # Globals
  20 $accuracy = $precision = undef;
  21 $round_mode = 'even';
  22 $div_scale = 40;
  23
  24 sub new
  25 {
  26         my $proto  = shift;
  27         my $class  = ref($proto) || $proto;
  28
  29         my $value       = shift;
  30         my $a = $accuracy; $a = $_[0] if defined $_[0];
  31         my $p = $precision; $p = $_[1] if defined $_[1];
  32         my $self = Math::BigFloat->new($value,$a,$p,$round_mode);
  33
  34 #       remember, downgrading may return a BigInt, so don't meddle with class
  35 #       bless $self,$class;
  36
  37         print "MBF new '$value' => '$self' (",ref($self),")";
  38         return $self;
  39 }
  40
  41 sub import
  42   {
  43   print "MBF import ",join(' ',@_);
  44   my $self = shift;
  45
  46   # we catch the constants, the rest goes go BigFloat
  47   my @a = ();
  48   foreach (@_)
  49     {
  50     push @a, $_ if $_ ne ':constant';
  51     }
  52   overload::constant float => sub { $self->new(shift); };
  53
  54   Math::BigFloat->import(@a);           # need it for subclasses
  55 #  $self->export_to_level(1,$self,@_);          # need this ?
  56   }
  57
  58 1;