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in reply to How to make bi-modal variables like $! ?

See SetDualVar, which includes XS code (C code) that sets the string/number value of a scalar without invalidating the other.

        - tye (but my friends call me "Tye")
  • Comment on (tye)Re: How to make bi-modal variables like $! ?

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Re: (tye)Re: How to make bi-modal variables like $! ?
by bikeNomad (Priest) on Jun 28, 2001 at 20:45 UTC
    Cool! Re-writing the guts of SetDualVar using Inline, it looks like:

    #!/usr/bin/perl -w
# Solution by Kenneth Albanowski <kjahds@kjahds.com>
# from the module SetDualVar-1.0.tar.gz 
# re-written using Inline.
use strict;
use Inline 'C';

my $v;
set_both($v, "I'm a string too!", 123);
print $v+0, " $v\n";

__END__
__C__
void set_both(SV* variable, SV* string, SV* numeric)
{
 SvPV(string, PL_na);
 if(!SvPOKp(string) || (!SvNOKp(numeric) && !SvIOKp(numeric)) ) {
  croak("Usage: set_both variable,string,numeric");
 }
 
 sv_setsv(variable,string);
 if(SvNOKp(numeric)) {
  sv_setnv(variable,SvNV(numeric));
 } else {
  sv_setiv(variable,SvIV(numeric));
 }
 SvPOK_on(variable);
}

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