=head1 NAME
-perlfaq3 - Programming Tools ($Revision: 1.40 $, $Date: 2004/10/19 17:02:27 $)
+perlfaq3 - Programming Tools ($Revision: 1.46 $, $Date: 2005/02/13 02:36:09 $)
=head1 DESCRIPTION
philosophy is the philosophy of several small tools that each do one
thing and do it well. It's like a carpenter's toolbox.
-If you want an IDE, check the following:
+If you want an IDE, check the following (in alphabetical order, not
+order of preference):
=over 4
+=item Eclipse
+
+The Eclipse Perl Integration Project integrates Perl
+editing/debugging with Eclipse.
+
+The website for the project is http://e-p-i-c.sf.net/
+
=item Komodo
-ActiveState's cross-platform (as of April 2001 Windows and Linux),
-multi-language IDE has Perl support, including a regular expression
+ActiveState's cross-platform (as of October 2004, that's Windows, Linux,
+and Solaris), multi-language IDE has Perl support, including a regular expression
debugger and remote debugging
-( http://www.ActiveState.com/Products/Komodo/ ). (Visual
-Perl, a Visual Studio.NET plug-in is currently (early 2001) in beta
-( http://www.ActiveState.com/Products/VisualPerl/index.html )).
+( http://www.ActiveState.com/Products/Komodo/ ).
=item Open Perl IDE
and debugging Perl scripts with ActiveState's ActivePerl distribution
under Windows 95/98/NT/2000.
+=item OptiPerl
+
+( http://www.optiperl.com/ ) is a Windows IDE with simulated CGI
+environment, including debugger and syntax highlighting editor.
+
=item PerlBuilder
( http://www.solutionsoft.com/perl.htm ) is an integrated development
( http://helpconsulting.net/visiperl/ )
From Help Consulting, for Windows.
-=item OptiPerl
+=item Visual Perl
+
+( http://www.activestate.com/Products/Visual_Perl/ )
+Visual Perl is a Visual Studio.NET plug-in from ActiveState.
-( http://www.optiperl.com/ ) is a Windows IDE with simulated CGI
-environment, including debugger and syntax highlighting editor.
=back
=item Affrus
-is a full Perl development enivornment with full debugger support (
-http://www.latenightsw.com ).
+is a full Perl development enivornment with full debugger support
+( http://www.latenightsw.com ).
=item Alpha
=head2 How can I free an array or hash so my program shrinks?
-You usually can't. On most operating systems, memory
-allocated to a program can never be returned to the system.
-That's why long-running programs sometimes re-exec
-themselves. Some operating systems (notably, systems that
-use mmap(2) for allocating large chunks of memory) can
-reclaim memory that is no longer used, but on such systems,
-perl must be configured and compiled to use the OS's malloc,
-not perl's.
-
-However, judicious use of my() on your variables will help make sure
-that they go out of scope so that Perl can free up that space for
-use in other parts of your program. A global variable, of course, never
-goes out of scope, so you can't get its space automatically reclaimed,
-although undef()ing and/or delete()ing it will achieve the same effect.
+(contributed by Michael Carman)
+
+You usually can't. Memory allocated to lexicals (i.e. my() variables)
+cannot be reclaimed or reused even if they go out of scope. It is
+reserved in case the variables come back into scope. Memory allocated
+to global variables can be reused (within your program) by using
+undef()ing and/or delete().
+
+On most operating systems, memory allocated to a program can never be
+returned to the system. That's why long-running programs sometimes re-
+exec themselves. Some operating systems (notably, systems that use
+mmap(2) for allocating large chunks of memory) can reclaim memory that
+is no longer used, but on such systems, perl must be configured and
+compiled to use the OS's malloc, not perl's.
+
In general, memory allocation and de-allocation isn't something you can
-or should be worrying about much in Perl, but even this capability
-(preallocation of data types) is in the works.
+or should be worrying about much in Perl.
+
+See also "How can I make my Perl program take less memory?"
=head2 How can I make my CGI script more efficient?
=head2 How can I compile my Perl program into byte code or C?
-Malcolm Beattie has written a multifunction backend compiler,
-available from CPAN, that can do both these things. It is included
-in the perl5.005 release, but is still considered experimental.
-This means it's fun to play with if you're a programmer but not
-really for people looking for turn-key solutions.
-
-Merely compiling into C does not in and of itself guarantee that your
-code will run very much faster. That's because except for lucky cases
-where a lot of native type inferencing is possible, the normal Perl
-run-time system is still present and so your program will take just as
-long to run and be just as big. Most programs save little more than
-compilation time, leaving execution no more than 10-30% faster. A few
-rare programs actually benefit significantly (even running several times
-faster), but this takes some tweaking of your code.
-
-You'll probably be astonished to learn that the current version of the
-compiler generates a compiled form of your script whose executable is
-just as big as the original perl executable, and then some. That's
-because as currently written, all programs are prepared for a full
-eval() statement. You can tremendously reduce this cost by building a
-shared I<libperl.so> library and linking against that. See the
-F<INSTALL> podfile in the Perl source distribution for details. If
-you link your main perl binary with this, it will make it minuscule.
-For example, on one author's system, F</usr/bin/perl> is only 11k in
-size!
-
-In general, the compiler will do nothing to make a Perl program smaller,
-faster, more portable, or more secure. In fact, it can make your
-situation worse. The executable will be bigger, your VM system may take
-longer to load the whole thing, the binary is fragile and hard to fix,
-and compilation never stopped software piracy in the form of crackers,
-viruses, or bootleggers. The real advantage of the compiler is merely
-packaging, and once you see the size of what it makes (well, unless
-you use a shared I<libperl.so>), you'll probably want a complete
-Perl install anyway.
+(contributed by brian d foy)
+
+In general, you can't do this. There are some things that may work
+for your situation though. People usually ask this question
+because they want to distribute their works without giving away
+the source code, and most solutions trade disk space for convenience.
+You probably won't see much of a speed increase either, since most
+solutions simply bundle a Perl interpreter in the final product
+(but see L<How can I make my Perl program run faster?>).
+
+The Perl Archive Toolkit (http://par.perl.org/index.cgi) is
+Perl's analog to Java's JAR. It's freely available and on
+CPAN (http://search.cpan.org/dist/PAR/).
+
+The B::* namespace, often called "the Perl compiler", but is really a
+way for Perl programs to peek at its innards rather than create
+pre-compiled versions of your program. However. the B::Bytecode
+module can turn your script into a bytecode format that could be
+loaded later by the ByteLoader module and executed as a regular Perl
+script.
+
+There are also some commercial products that may work for
+you, although you have to buy a license for them.
+
+The Perl Dev Kit
+(http://www.activestate.com/Products/Perl_Dev_Kit/) from
+ActiveState can "Turn your Perl programs into ready-to-run
+executables for HP-UX, Linux, Solaris and Windows."
+
+Perl2Exe (http://www.indigostar.com/perl2exe.htm) is a
+command line program for converting perl scripts to
+executable files. It targets both Windows and unix
+platforms.
+
=head2 How can I compile Perl into Java?
interpreter, NT people can use: C<SET PATHEXT=%PATHEXT%;.PL> to let them
run the program C<install-linux.pl> merely by typing C<install-linux>.
-Macintosh Perl programs will have the appropriate Creator and
-Type, so that double-clicking them will invoke the Perl application.
+Under "Classic" MacOS, a perl program will have the appropriate Creator and
+Type, so that double-clicking them will invoke the MacPerl application.
+Under Mac OS X, clickable apps can be made from any C<#!> script using Wil
+Sanchez' DropScript utility: http://www.wsanchez.net/software/ .
I<IMPORTANT!>: Whatever you do, PLEASE don't get frustrated, and just
throw the perl interpreter into your cgi-bin directory, in order to
how the authors of existing extension modules wrote their code and
solved their problems.
-=head2 I've read perlembed, perlguts, etc., but I can't embed perl in
-my C program; what am I doing wrong?
+=head2 I've read perlembed, perlguts, etc., but I can't embed perl in my C program; what am I doing wrong?
Download the ExtUtils::Embed kit from CPAN and run `make test'. If
the tests pass, read the pods again and again and again. If they
=head1 AUTHOR AND COPYRIGHT
-Copyright (c) 1997-2002 Tom Christiansen and Nathan Torkington.
-All rights reserved.
+Copyright (c) 1997-2005 Tom Christiansen, Nathan Torkington, and
+other authors as noted. All rights reserved.
This documentation is free; you can redistribute it and/or modify it
under the same terms as Perl itself.
projects / p5sagit/p5-mst-13.2.git / blobdiff