Acme::SvGROW - syntax for pre-extending a string's storage,

Acme-SvGROW documentation

Contained in the Acme-SvGROW distribution.

Index

NAME
SYNOPSIS
DESCRIPTION
EXPORT
SEE ALSO
CHANGES
- 0.03
AUTHOR
COPYRIGHT AND LICENSE

Code Index:

package Acme::SvGROW
__END__
EOF

NAME

Acme::SvGROW - syntax for pre-extending a string's storage, like the proposed use of length as an L-value

SYNOPSIS

  use Acme::SvGROW;
  SvGrow($BigString, 100000);
  # when l-value subroutines are available (5.8 and later)
  SvGrow($BigString, 100000) = InitialValueOfBigString();

DESCRIPTION

Trivial module implementing string storage preallocation using techniques shared on perl5-porters mailing list November 4 and 5, 2009

EXPORT

the SvGROW subroutine is exported. It takes two arguments, the first the string to extend and the second the length.

SEE ALSO

perlguts

Data::Peek for a benchmarking of the alternatives

The author of this module is in favor of allowing length to be used as an lvalue to thinly invoke the SvGROW internals macro

CHANGES

0.03

Data::Peek::DGrow will be used if available

AUTHOR

David Nicol davidnico@cpan.org

COPYRIGHT AND LICENSE

Public domain: use at will.

Acme-SvGROW documentation

Contained in the Acme-SvGROW distribution.

package Acme::SvGROW;

require Exporter;
@ISA = qw(Exporter);

@EXPORT = qw(
	SvGROW	
);

$VERSION = '0.03';
if (eval <<'dgrowp'
   use Data::Peek 'DGrow';
   1;
dgrowp
){
   eval <<'LVAL' or eval <<'NOLVAL' or die "DGrow sub failed: $@"

     sub SvGROW($$) : lvalue {
        DGrow($_[0],$_[1]);
        $_[0]
     }
     1;
LVAL

     sub SvGROW($$) {
        DGrow($_[0],$_[1]);
        $_[0]
     }
NOLVAL

}
else
{
   eval <<'LVAL' or eval <<'NOLVAL'

     sub SvGROW($$) : lvalue {
        my $tmp = $_[0];
        $_[0] = pack 'x'.int(0+$_[1]);
        $_[0] = $tmp;
        $_[0]
     }
     1;
LVAL

     sub SvGROW($$) {
        my $tmp = $_[0];
        $_[0] = pack 'x'.int(0+$_[1]);
        $_[0] = $tmp;
        $_[0]
     }
NOLVAL

};

1;
__END__