Inline::Pdlapp - Write PDLA Subroutines inline with PDLA::PP


Inline::Pdlapp is a module that allows you to write PDLA subroutines in the PDLA::PP style. The big benefit compared to plain PDLA::PP is that you can write these definitions inline in any old perl script (without the normal hassle of creating Makefiles, building, etc). Since version 0.30 the Inline module supports multiple programming languages and each language has its own support module. This document describes how to use Inline with PDLA::PP (or rather, it will once these docs are complete ;).

For more information on Inline in general, see Inline.

Some example scripts demonstrating Inline::Pdlapp usage can be found in the examples directory.

Inline::Pdlapp is a subclass of Inline::C. Most Kudos goes to Brian I.


You never actually use Inline::Pdlapp directly. It is just a support module for using with PDLA::PP. So the usage is always:

    use Inline Pdlapp => ...;


    bind Inline Pdlapp => ...;


Pending availability of full docs a few quick examples that illustrate typical usage.

A simple example

   # example script
   use PDLA; # must be called before (!) 'use Inline Pdlapp' calls

   use Inline Pdlapp; # the actual code is in the __Pdlapp__ block below

   $a = sequence 10;
   print $a->inc,"\n";
   print $a->inc->dummy(1,10)->tcumul,"\n";



          Pars => 'i();[o] o()',
          Code => '$o() = $i() + 1;',

          Pars => 'in(n);[o] mul()',
          Code => '$mul() = 1;
                   loop(n) %{
                     $mul() *= $in();
   # end example script

If you call this script it should generate output similar to this:

   prompt> perl
   Inline running PDLA::PP version 2.2...
   [1 2 3 4 5 6 7 8 9 10]
   [3628800 3628800 3628800 3628800 3628800 3628800 3628800 3628800 3628800 3628800]

Usage of Inline::Pdlapp in general is similar to Inline::C. In the absence of full docs for Inline::Pdlapp you might want to compare Inline::C.

Code that uses external libraries, etc

The script below is somewhat more complicated in that it uses code from an external library (here from Numerical Recipes). All the relevant information regarding include files, libraries and boot code is specified in a config call to Inline. For more experienced Perl hackers it might be helpful to know that the format is similar to that used with ExtUtils::MakeMaker. The keywords are largely equivalent to those used with Inline::C. Please see below for further details on the usage of INC, LIBS, AUTO_INCLUDE and BOOT.

   use PDLA; # this must be called before (!) 'use Inline Pdlapp' calls

   use Inline Pdlapp => Config =>
     INC => "-I$ENV{HOME}/include",
     LIBS => "-L$ENV{HOME}/lib -lnr -lm",
     # code to be included in the generated XS
   #include <math.h>
   #include "nr.h"    /* for poidev */
   #include "nrutil.h"  /* for err_handler */

   static void nr_barf(char *err_txt)
     fprintf(stderr,"Now calling croak...\n");
     croak("NR runtime error: %s",err_txt);
   # install our error handler when loading the Inline::Pdlapp code
   BOOT => 'set_nr_err_handler(nr_barf);';

   use Inline Pdlapp; # the actual code is in the __Pdlapp__ block below

   $a = zeroes(10) + 30;;
   print $a->poidev(5),"\n";



           Pars => 'xm(); [o] pd()',
           GenericTypes => [L,F,D],
           OtherPars => 'long idum',
           Code => '$pd() = poidev((float) $xm(), &$COMP(idum));',


It is possible, using Inline::Module, to create an installable .pm file with inline PDLA code. PDLA::IO::HDF is a working example. Here's how. You make a Perl module as usual, with a package declaration in the normal way. Then (assume your package is PDLA::IO::HDF::SD):

  package PDLA::IO::HDF::SD;
  # ...
  use FindBin;
  use Alien::HDF4::Install::Files;
  use PDLA::IO::HDF::SD::Inline Pdlapp => 'DATA',
    package => __PACKAGE__, # if you have any pp_addxs - else don't bother
    %{ Alien::HDF4::Install::Files->Inline('C') }, # EUD returns empty if !"C"
    typemaps => "$FindBin::Bin/lib/PDLA/IO/HDF/typemap.hdf",
  # ...
  /* ... */
  use FindBin;
  use lib "$FindBin::Bin/../../../../../../..";
  require 'buildfunc.noinst';
  # etc

Note that for any files that you need to access for build purposes (they won't be touched during post-install runtime), FindBin is useful, albeit slightly complicated.

In the main .pm body, FindBin will find the build directory, as illustrated above. However, in the "inline" parts, FindBin will be within the Inline::Module build directory. At the time of writing, this is under .inline within the build directory, in a subdirectory named after the package. The example shown above has seven ..: two for .inline/build, and five more for PDLA/IO/HDF/SD/Inline.

The rest of the requirements are given in the Inline::Module documentation.

This technique avoids having to use PDLA::Core::Dev, create a Makefile.PL, have one directory per .pd, etc. It will even build / install faster, since unlike a build of an ExtUtils::MakeMaker distribution with multiple directories, it can be built in parallel. This is because the EUMM build changes into each directory, and waits for each one to complete. This technique can run concurrently without problems.


For information on how to specify Inline configuration options, see Inline. This section describes each of the configuration options available for Pdlapp. Most of the options correspond either to MakeMaker or XS options of the same name. See ExtUtils::MakeMaker and perlxs.


Specifies extra statements to automatically included. They will be added onto the defaults. A newline char will be automatically added. Does essentially the same as a call to pp_addhdr. For short bits of code AUTO_INCLUDE is probably syntactically nicer.

    use Inline Pdlapp => Config => AUTO_INCLUDE => '#include "yourheader.h"';


Same as pp_bless command. Specifies the package (i.e. class) to which your new pp_defed methods will be added. Defaults to PDLA if omitted.

    use Inline Pdlapp => Config => BLESS => 'PDLA::Complex';

cf "PACKAGE", equivalent for "pp_addxs" in PDLA::PP.


Specifies C code to be executed in the XS BOOT section. Corresponds to the XS parameter. Does the same as the pp_add_boot command. Often used to execute code only once at load time of the module, e.g. a library initialization call.


Specify which compiler to use.


Specify extra compiler flags.


Specifies an include path to use. Corresponds to the MakeMaker parameter.

    use Inline Pdlapp => Config => INC => '-I/inc/path';


Specify which linker to use.


Specify which linker flags to use.

NOTE: These flags will completely override the existing flags, instead of just adding to them. So if you need to use those too, you must respecify them here.


Specifies external libraries that should be linked into your code. Corresponds to the MakeMaker parameter.

    use Inline Pdlapp => Config => LIBS => '-lyourlib';


    use Inline Pdlapp => Config => LIBS => '-L/your/path -lyourlib';


Specify the name of the 'make' utility to use.


Specifies a user compiled object that should be linked in. Corresponds to the MakeMaker parameter.

    use Inline Pdlapp => Config => MYEXTLIB => '/your/path/';


This controls the MakeMaker OPTIMIZE setting. By setting this value to '-g', you can turn on debugging support for your Inline extensions. This will allow you to be able to set breakpoints in your C code using a debugger like gdb.


Controls into which package the created XSUBs from "pp_addxs" in PDLA::PP go. E.g.:

    use Inline Pdlapp => 'DATA', => PACKAGE => 'Other::Place';

will put the created routines into Other::Place, not the calling package (which is the default). Note this differs from "BLESS", which is where "pp_def" in PDLA::PPs go.


Specifies extra typemap files to use. Corresponds to the MakeMaker parameter.

    use Inline Pdlapp => Config => TYPEMAPS => '/your/path/typemap';


Show the output of any compilations going on behind the scenes. Turns on BUILD_NOISY in Inline::C.


doing inline scripts

Beware that there is a problem when you use the __DATA__ keyword style of Inline definition and want to do your script containing inlined code. For example

   # contains inlined code
   # in the __DATA__ section
   perl -e 'do "";'
 One or more DATA sections were not processed by Inline.

According to Brian Ingerson (of Inline fame) the workaround is to include an Inline->init call in your script, e.g.

  use PDLA;
  use Inline Pdlapp;

  # perl code


  # pp code

PDLA::NiceSlice and Inline::Pdlapp

There is currently an undesired interaction between PDLA::NiceSlice and Inline::Pdlapp. Since PP code generally contains expressions of the type $var() (to access piddles, etc) PDLA::NiceSlice recognizes those incorrectly as slice expressions and does its substitutions. For the moment (until hopefully the parser can deal with that) it is best to explicitly switch PDLA::NiceSlice off before the section of inlined Pdlapp code. For example:

  use PDLA::NiceSlice;
  use Inline::Pdlapp;

  $a = sequence 10;

  no PDLA::NiceSlice;



  ppdef (...); # your full pp definition here


Brian Ingerson for creating the Inline infrastructure.


Christian Soeller <>




Copyright (c) 2001. Christian Soeller. All rights reserved.

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