# man > ExtUtils::Typemaps::OutputMap

## NAME
    [ExtUtils::Typemaps::OutputMap](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3ATypemaps%3A%3AOutputMap/markdown) - Entry in the OUTPUT section of a typemap

## SYNOPSIS
      use [ExtUtils::Typemaps](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3ATypemaps/markdown);
      ...
      my $output = $typemap->get_output_map('T_NV');
      my $code = $output->code();
      $output->code("...");

## DESCRIPTION
    Refer to [ExtUtils::Typemaps](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3ATypemaps/markdown) for details.

## METHODS
  new
    Requires "xstype" and "code" parameters.

  code
    Returns or sets the OUTPUT mapping code for this entry.

  xstype
    Returns the name of the XS type of the OUTPUT map.

  cleaned_code
    Returns a cleaned-up copy of the code to which certain transformations have been applied to make
    it more ANSI compliant.

  targetable
    This is an obscure but effective optimization that used to live in "[ExtUtils::ParseXS](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3AParseXS/markdown)" directly.
    Not implementing it should never result in incorrect use of typemaps, just less efficient code.

    In a nutshell, this will check whether the output code involves calling "sv_setiv", "sv_setuv",
    "sv_setnv", "sv_setpv" or "sv_setpvn" to set the special $arg placeholder to a new value AT THE
    END OF THE OUTPUT CODE. If that is the case, the code is eligible for using the "TARG"-related
    macros to optimize this. Thus the name of the method: "targetable".

    If this optimization is applicable, "[ExtUtils::ParseXS](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3AParseXS/markdown)" will emit a "dXSTARG;" definition at the
    start of the generated XSUB code, and type (see below) dependent code to set "TARG" and push it
    on the stack at the end of the generated XSUB code.

    If the optimization can not be applied, this returns undef. If it can be applied, this method
    returns a hash reference containing the following information:

      type:      Any of the characters i, u, n, p
      with_size: Bool indicating whether this is the sv_setpvn variant
      what:      The code that actually evaluates to the output scalar
      what_size: If "with_size", this has the string length (as code,
                 not constant, including leading comma)

## SEE ALSO
    [ExtUtils::Typemaps](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3ATypemaps/markdown)

## AUTHOR
    Steffen Mueller "<<smueller@cpan.org>">

COPYRIGHT & LICENSE
    Copyright 2009, 2010, 2011, 2012 Steffen Mueller

    This program is free software; you can redistribute it and/or modify it under the same terms as
    Perl itself.