Hmm. There seem to be two interacting problems here.
- exp doesn't appear to be overloaded by either bignum or Math::BigFloat?
#!perl -slw
use strict;
use overload;
#use bignum;
use Math::BigFloat;
printf "exp(-7e-17): %.17f\n", my $exp = exp( Math::BigFloat->new( '-7
+e-17' ) );
eval{ print overload::Overloaded( $exp ) } or warn $@;
print overload::StrVal( $exp );
printf "1-exp(-7-e17): %.17f\n", Math::BigFloat->new("1") - $exp;
__END__
C:\test>junk7
exp(-7e-17): 0.99999999999999989
Can't call method "can" without a package or object reference at c:/Pe
+rl/lib/overload.pm line 54.
1
1-exp(-7-e17): 0.00000000000000000
- And with bignum enabled, Math::BigFloat seems to forget how to do math? At least if the math involves one BigMath object and one normal perl number.
#!perl -slw
use strict;
use overload;
use bignum;
use Math::BigFloat;
printf "exp(-7e-17): %.17f\n", my $exp = exp( Math::BigFloat->new( '-7
+e-17' ) );
eval{ print overload::Overloaded( $exp ) } or warn $@;
print overload::StrVal( $exp );
printf "1-exp(-7-e17): %.17f\n", Math::BigFloat->new("1") - $exp;
__END__
C:\test>junk7
exp(-7e-17): 0.99999999999999989
Can't call method "can" without a package or object reference at c:/Pe
+rl/lib/overload.pm line 54.
1
1-exp(-7-e17): 1.00000000000000000
All of which makes me glad that I rarely need the accuracy beyond 53-bits and when I do, 64-bit ints suffice.
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