Where did CORE::cos go? was: Re: RFC: BigInt and overloading of sin/cos

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Moin,

On Saturday 25 October 2003 21:23, Tels wrote:
> Moin,
>
> I got a bugreport from Dennis Boylan:
>
> 	# perl -Mbigint -le 'print cos(4)'
> 	Operation `cos': no method found, argument in overloaded package
> Math::BigInt at -e line 1.

I opted no to the following plan:

* Add an option ':fallback' to BigInt, which tricks overload to make 
cos(Math::BigInt->new(1)) equivalent to cos(1)
* add option to Math::Big to overload cos(), sin(), atan2() and exp() so that 
they produce BigFloats.

So:

* default BigInt dies with "no method found.
* use BigInt ':fallback'; is equivalent to no BigInt at all AFA 
cos/sin/atan/exp are concerned (e.g. cos(1) returns 0.54etc to 10 digits 
approcimately)
* use BigInt ':fallback'; use Math::Big qw/:cos :sin :atan2 :exp/; will 
produce BigFloats (selectively)

There is only one snag:

te@null:~> cat cos.pl
#!/usr/bin/perl -w

package Test;

# without the "''" nomethod is never called
use overload
  '""' => sub { $$_[0]} ;

sub new
  {
  my $a = $_[0];
  bless \$a, 'Test';
  }

sub import
  {
  overload->import (
    nomethod => sub {
          &{'sCORE::' . $_[3]}( $_[0], $_[1], $_[2] );
          print "nomethod ", join(":", @_), "\n";
          },
    );
  }

package main;

use Test;

print CORE::cos(1),"\n";
print cos(Test->new(1)),"\n";

te@null:~> perl cos.pl
0.54030230586814
Undefined subroutine &sCORE::cos called at cos.pl line 18.

I tried UNIVERSAL::cos, main::cos etc, but they all come back as "undefined". 
However, a plain "CORE::cos" works just fine. What do I do wrong? *puzzled*

Best wishes,

Tels

- -- 
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• RFC: BigInt and overloading of sin/cos by Tels
• Re: RFC: BigInt and overloading of sin/cos by Tels
• Where did CORE::cos go? was: Re: RFC: BigInt and overloading of sin/cos by Tels
• Re: Where did CORE::cos go? was: Re: RFC: BigInt and overloading of sin/cos by Tels