perl

Perl offers a rich set of modules and libraries for the XML developer, rivaling that of any other language.

The syntax itself was similar to that of Perl, albeit much more limited, simple, and somewhat inconsistent.

The point of Perl 5 regular expressions is to say either "look for this, " or "look for this and replace it with that. "

This is no "Learning Perl" material; at least a few years of programming experience are necessary to get through the rest of the book.

In a bit of Perl shorthand, the array of field names and the array of parsed fields is combined into a hash.

The code must select only ELEMENT type nodes, because TEXT nodes do not support this method and produce a non-recoverable error in Perl.

Perl is often thought of as a Swiss Army Knife or a large roll of duct tape.

Python is object oriented, which gives it a significant advantage over such other scripting languages as Perl and Rexx.

Its creator, Guido van Rossum, wanted a language that, like Perl, would make it easy to do easy tasks yet also support hard tasks.

In PERL, the MIME type is set by writing it out at the start of the page, before any other content.

The downside of these approaches is, of course, that the Perl programmer will pick one of these and disregard the others.

My post seems to have pissed of a lot of Perl fans, and in retrospect I realized that I was harsher on the language than I should have been.

Although it is possible to write advanced sorting applications in Perl or Awk, doing so may not always be necessary -- and is often a pain.

Note, however, that, unlike C or Perl, Vimscript does not allow you to throw away the return value of a function without using it.

If you've been doing any shell or Perl scripting at all, you know you can capture the output of other commands inside backtick operators.

So, in this article I'm going to look at some of the key techniques you can use to squeeze those extra cycles out of your Perl application.

Remember: it's just a few extra lines of the Perl (or Python, or . . . ) code you already know to give these results.

There is no way or need to turn this feature off, but novice Perl programmers can create new exciting bugs with it in a matter of hours.

With your custom Sphinx-4 speech recognition and the annotateAcrNum Perl program, you're ready to start annotating spoken conversations.

Note, however, that this doesn't convert the Perl into C, it just embeds Perl bytecode into a C-based application.

local was very easy to implement, and was added to Perl 4 as a partial solution to the local variable problem.

Neither of the above examples truly shows off the true power of either Perl or Python, nor was that my intent in a short article.

Providing you know the Perl opcodes, you can begin to identify where the potential bottlenecks might be.

Python is roughly comparable to Perl or Java, though it has several significant strengths (and a few disadvantages) over each.

MRTG to use complex operations are command line format, perl support PRTG and provide graphical wizard, easy to use.

Novice Perl programmers notice right away that there seems to be no compilation.

In terms of embedded Perl code, the things you always need are a "noun" (the thing affected) and a "verb" (the action taken).

Perl has traditionally been a text-oriented language, so Unicode support changes the very core of the language.

If you thought "Hey, why just Perl? " when you read this article, you were not the only one.

For more detailed information about portability problems, take a look at Perl Programming Documentation (see Resources for a link).

Before diving in, it's worth mentioning that this article is intended for intermediate-level Perl programmers.

The use of that module is beyond the scope of this article, but we recommend it for greater precision when parsing Perl codes.

To be fair, Perl also retains this distinction, but deals with it in typical Perl fashion by letting you omit returns.

And, with Perl, you've got a full range of programming constructs you can take advantage of for doing even more complex text processing.

Perl hides this layer of complexity from us, creating a sort of encapsulation very similar to what exists in OOP.

Easy to use perl scripts that help you monitor file or directory modifications.

One of the lesser-known solutions for both debugging and optimizing your code is to use the Perl compiler with one of the many "back ends. "

Perl and the GD modules have been used together for many years to create useful dynamic charts and graphics for Web sites and presentations.

If you do not care about how the Perl script works and just want to install it, skip to the next section.

Perl supports multiple inheritance, though two or more parents are rarely seen in practice.

I hope to see more of those topics in the next edition of the Perl 6 Essentials book.

If it seems like I'm harping on readability, it's for a good reason: new Perl programmers are intimidated by Perl 5 regular expressions.

Moreover (at least to me), Ruby achieves conciseness while still avoiding the "executable line noise" quality found in some Perl code.

It's easy to read and very thorough; using it from Perl is simple.

At this point all the steps will be in place to create a Perl script which accesses a Derby database.

In fact, the name "Perl" really has no special meaning.

It may have been installed elsewhere; consult with your local Perl administrator if you can't find that directory.

The chapter on objects is a longer, more detailed exposition of OO in Perl, though it is still somewhat neglected in the book as a whole.

Building Perl projects with MakeMaker is no different than any other aspect of Perl: there are many ways to do it.

The solution is to use AutoLoader, which acts a bit like a dynamic loader for Perl modules.

From the command line Perl can accomplish, in just a single line, tasks that require pages of code in most other languages.

For the programmers who want Perl to be a more functional language, map and grep can satisfy the craving.

You're always allowed to include the package part of the variable's name, and if you do, Perl will know exactly which variable you mean.

Don't let the name fool you; this really is Perl's XML-RPC library, which for historical reasons has this unexpected name.

Perl makes it easy to convert numbers into strings and vice versa, but that can create subtle bugs that take hours or days to find.

Maybe you write a few Perl scripts or know someone who will provide you with some code for this or a procedure for that.

No one who works with UNIX for any length of time can avoid eventually writing some Perl code.

Also, you need to be aware of the potential speed impact of any statement, much more so than in C.

Table 2 lists Perl core functions and operators leveraged to call system commands from within a Perl script.

This line of thinking will then lead you to a module called perlmodule, which lets you embed a Perl interpreter in Python.

The pattern matching chapter is sufficient for learning about this fascinating side of Perl.

It's a very complete summary of what you can expect in Perl 6, and if I had to pick just one chapter out of the book, this is it.

Perl used to be the recommendation, but Python is now quite mature, and is possibly easier to learn.

Double quotes in Perl serve to interpret everything between them.

Perl programmers should use File: : Temp, which tries to provide a cross-platform means of securely creating temporary files.

Also like the Perl library, PHP allows the programmer to look at the underlying XML-RPC conversation for debugging.

The syntax of YAML combines the contextual typing of Perl, the indentation structure of Python, and a few conventions from MIME standards.

As you can see from the diagram, a Perl program uses a standard API to communicate with DBI, the database interface module for Perl.

Scripting languages like AppleScript or Perl are often the best choice for writing this part of the fuzz test.

Bizarrely, the color of the list box cannot be changed -- unless one wants to edit the code of the underlying Perl module.

Linux, Apache, MySQL, and PHP (or Perl) are the foundation of many Web applications, from to-do lists to blogs to e-commerce sites.

Perl scripts and Java scripts provide free downloading of scripts in Perl and Java as the name suggests.

You could use Perl to produce custom-tailored cfengine configurations, or you could run Perl scripts from cfengine.

Before you do that, there are a few other documents that are usually distributed with perl code.

The Perl way is that programmers should be allowed to break the rules in the interest of coding, debugging, and execution efficiency.

The company also has a pay-ware module written in Perl, designed for HTTP compression with both the IIS and Apache Web servers.

Listing 2 shows a simple Perl script used to display the memory size of a Solaris system.

The fact that Class: : DBI simplifies record operations to one-liners makes embedding Perl code in the database feasible and palatable.

Indeed, given its prevalence in Python, Perl, and Apache projects, expat is clearly one of the most widely-used XML parsers available.

Tom Christiansen posted a list of one-liners on Usenet years ago, and that list is still interesting and useful for any Perl programmer.

If the front end is written in Perl or PHP, it is tempting to hard code access to MySQL in the CGI scripts.

Any front-end will work: the parser can be accessed as a regular Perl function, and can access other regular Perl functions and modules.

Perl would be Voodoo - An incomprehensible series of arcane incantations that involve the blood of goats and permanently corrupt your soul.

It's hardly famous as a business hub, but this article shows some ways to use Flickr through Perl that are more business oriented.

It can be applied to much larger problems than languages such as Awk or even Perl can, yet it remains as easy to use as those languages.

I took a very superficial look at some of the common features and differences in two of the more popular languages, Perl and Python.

Perl is a very tried and true language, it's been around since the late eighties, but PHP is maturing very quickly.

This is the main Perl program that allows you to create tonal sequences, as well as listen for specific tonal sequences and run commands.

The return value from the remote procedure is converted into a standard Perl scalar by call and printed.

This is the main Perl program that allows you to create knock sequences as well as listen for specific knock sequences and run commands.

HOP is a terrific book targeted at the advanced Perl programmer with a significant computer science background.

I felt like a kid in a candy store reading about junctions, currying, and all the other exciting features that Perl 6 promises.

Many of the tasks Perl was first used for included text processing and system administration tasks.

But start to include a few of your own external modules and the time increases.

Perl often bewilders even experienced programmers, primarily because it allegedly makes it too easy to write obfuscated code.

The POE module provides one of the easiest ways to create bidirectional TCP communications using Perl.

As I did not specify PREFIX in my Makefile. PL, this variable will be gathered from my perl interpreter.

Learn to understand the Perl notation for anonymous array references and dereferencing array elements.

Let's first look at a simple implementation of this model for a fictitious Perl program.

This will build all of the perl binaries and libraries into a temporary blib directory.

Why invent another set of OS names, when Perl figures out the OS name for you?

Markdown is a text-to-HTML conversion tool initially written in Perl by John Gruber who released it back in 2004 under a BSD license.

Another Perl script with its own custom database files, of course.

You can pass as many arguments as you want to Perl, unless your shell limits their number or length.

URL pattern: a Perl-compatible regular expression string to be matched with the URL sent by the client.

The intended audience of the Perl 6 Essentials book is not the entire Perl community, but it does include anyone interested in Perl 6.

My path never took me too far down the Perl road, but I taught myself Python using the excellent and free online book, Dive into Python.

The return value from the remote procedure is converted into a standard Perl scalar by.

The examples above demonstrate how straightforward it is to "GUIfy" with a few extra lines of Perl.

The quintessential quality of a Perl programmer is productive laziness (or lazy productivity).

This tool consists of a set of Perl scripts that build on the text-based gcov output to implement HTML-based output.

Whether I have the guts to do Perl again is another question. My guts are still in sad shape at the moment, according to the doctor. . .

But unlike C, Perl steals some of those arguments from the script for its own purposes.

You cannot use the usual Perl print routines to display the error message, because you need the message to be displayed inside Vim.

Meanwhile, the Perl programmers are giving them glasses of water just because, well, that's the kind of nice people we are.

The page refers to it as a structured data type similar to variables in Python or Perl.

Again, note how Perl was an intermediate tool between find, sort and uniq.

The errstr method returns a message for an SQLCODE associated with a Perl DBI database handle or statement handle.

Perl is a great tool that allows you to search an entire file system quickly.

This is what I meant earlier when I said that you should know Perl well before starting on the one-liners.

As you may expect from a scripting language, the Perl client is brief.

Perl is now one of the most popular programming language in the world. .

And I don't want you to think that I completely shun Perl.

Later we added two more modules, an image generator written in C, and a back-office manager written mostly in Perl.

We will use MPlayer and a simple Perl script to automate the extraction of frames from the source files into jpeg files on disk.

The "-e" argument to Perl tells it to take whatever follows the "-e" on the command line and run it as a script.

It would have been nice if the recipes were marked with the version of Perl that supports them.

The Pixie module takes a different approach to interfacing your Perl project with a relational database.

Perl, who stressed that he was speaking as an experienced neuropathologist and not on behalf of the Department of Defense.

GA in Perl is useful as a teaching tool, to prototype complex GA simulations, and to run small GA simulations.

The Perl Monks Web site provided the incantation used in this article to clean up script output and has many other great tips for Perl fans.

You'll also need the File: : Find module (standard with most Perl distributions) for working with LDAP data files on your system.

Reference counting is used quite a bit in high-level languages like Perl to do memory management.

I recommend it to all Perl programmers, and I think beginner programmers will find the first 6 chapters especially useful.

If you want to shoot yourself in the foot, Perl will give you ten bullets and a laser scope, then stand by and cheer you on.

Start the application with perl hdapsGoogleStreetView. pl, and you'll be able to navigate city streets with tilts and rolls.

This means that you need a solid understanding of the interaction of references, hashes, and arrays in Perl.

You need to be aware of any Perl commands that manipulate files.

The main issue with wxPerl is translating the wxWidgets API into Perl's somewhat idiosyncratic flavor of object-oriented programming (OOP).

In this installment, prepare to witness a full mod_perl site (code only; templates are in the next part).

POD markup text is considered a comment by the Perl interpreter, so you may have POD documentation distributed throughout your code.

As soon as you install Perl, you start to realize just how many modules make up the "base" installation of the language.

One way around this is to use the Cygwin compatibility layer and a Perl built against that, in which case the compiler will be gcc.

Please use the exercise from Lab #4 to write and execute a Perl program that will retrieve a binary large object from a table into a file.

Then it shouldn't be too hard to put this under subversion control or write a small perl script to merge those files.

The tool requires a Perl interpreter to be installed on the system where it is run.

I used a Perl script, replace. pl, which replaces a keyword by its corresponding value found in the parameters. xml in a given file.

A separate Perl script is used to determine what files in the backup preparation directory can be deleted.

Perl scripts are provided to help you collect and analyze the DB2 snapshot data and to provide hints to improve database performance.

The Perl compiler works by taking the generated bytecode and then outputting the results in a variety of different ways.

To run the script, the . pl extension should be associated with the Perl executable.

Then what has probably happened is that you updated Perl to a new version and now storable-pm needs to be updated.

Similarly, Perl was designed to be a mess (though in the nicest of possible ways).

Line and comment out the second, you ll see that Perl sorts the input data consistently.

There are no special variables of the kind that good Perl programmers use regularly.

Regexps are also popularly used in the Perl language, but Perl regexps are different from those you'd build using grep.

In particular, setting up a full mod_perl site and using the Template Toolkit are broad topics, so I won't explain it all in this series.

It's a Perl 5 module that can produce very powerful grammars with just a little code.

Perl's -p option tells it to read and process each line from standard input and print the results to standard output.

To emphasize the open, cross-platform nature of SOAP applications, I will look at clients written in Perl, Python, and PHP.

Perl 6 grammars and regular expressions allow non-grouping matches, which do not save their result.

If the form is generated from a reused mod_perl instance, the PID number will not necessarily change between invocations.

The Perl script in Listing 2 checks to see if you have the required Perl modules installed on your system.

Solaris-specific resources, most notably operating system pathnames, system commands, and Perl modules, are often leveraged in the code.

And I also showed two Perl implementations, one that bred bytes and another that bred words.

Readers with intermediate to advanced Perl skills will definitely find this book more useful.

It supports CGI with a built-in Perl interpreter, virtual hosting, IPv6, bandwidth management, and security features.

What this does is save Perl from having to compile the script from its source code into the bytecode each time.

On Windows servers, the script should be directly executable if the . pl file extension has been associated with the Perl executable.

Module and MySQL to introduce you to embedding Perl in database tables.

Other arguments (the attribute and name arguments to set needn't do any kind of Perl gyrations and can treat strings as normal C strings).

You used a set of Perl scripts to migrate user account information into the LDAP directory.

For instance, the script being interpreted does not see the "-w" parameter to the Perl interpreter, unless the script appears to want it.

For any document the Perl programmer must make available a set of handler methods, one for each type of event.

It demonstrates a Perl program that connects to database SAMPLE with user ID and password that are passed to the program as parameters.

A perl script that aids in compiling module sources into Dynamic Shared Objects (DSOs) and helps install them in the Apache Web server.

perl tbs_usage. pl - This script provides the free and used space for all the tablespaces for a given database.

So you should expect to have to make some code remediation to ensure that Perl scripts work as intended after the migration.

Makefile. PL is a Perl script that generates a gnu Makefile for your entire project.

Match Expression: Perl-compatible regular expression that matches against the value of the header.

Currently, the activation engine only supports scripts written in PERL and Shell, with the postfixes . pl and . sh, respectively.

This is one of the many problems that you just shouldn't solve entirely in Perl, unless you are very ambitious.

An example of the XSLT, producing the same basic output as provided by the Perl script, is shown in Listing 5.

On other platforms, make sure the shebang line points to where your Perl executable actually lives or else the script will not run.

An interpreted language, Perl can be used in stand-alone applications or with Apache to build Web applications.

This difference makes P: : RD much more effective than Perl 5 regular expressions at making something happen when a match is detected.

This interface allows scripts written in Perl to access and manipulate information stored in Adaptive Server Anywhere databases.

Is a comprehensive set of Perl modules for genetic algorithm programming.

The second, Shutter, is a Perl script that provides a great user interface for specifying, selecting, and managing screen captures.

On the controller side, Apache's mod_perl interface is a good way of interacting with Perl-based Web applications.

It enforces coding conventions by following simple regular expression usage and moves on to Perl scripting with Vim.

The MLDBM module allows complex Perl hashes to be almost seamlessly stored in a local file.

Most people are familiar with CPAN as an interactive shell for building and installing Perl modules.

The syntax uses PRCE (Perl Compatible Regular Expressions), a very powerful way of matching any desired string pattern.

This program is not as terse as the Perl version and does not have the special variables and assumptions.

But things have finally changed, thanks to two Perl hackers and a lot of volunteer help and contributions!

OOP purists feel that everything should be classified properly, but Perl programmers are not purists by any means.

Perl has a feature like Taint mode built into it that can be used for such security checks.

If the in-memory data structure has a name for the root element, add a KeepRoot option, setting it to true, or as it's known in Perl, 1.

Nevertheless, some hope exists; after all, we just looked at some ways in which Perl can simplify system administration.

But Perl provides a large number of tools for quite complicated problems, including systems programming.

The Sample module and its documentation are wonderful tools for any Perl programmer at Sample.

Regardless of my views, Perl has become one of the most powerful (and at times arcane) scripting languages.

The technique to return a result set (or multiple results) from a database into a Perl program is pretty much the same.

If you want to understand Perl 6 grammars, you'll have to learn more about lexing and parsing that you probably ever wanted to.

Perl-based approaches to application configuration range from XML or YAML to the Getopt module to Perl code in the configuration file.

In the two argument case, ok will generate "ok" if the two arguments are equal as tested by the perl "eq" operator.

PHP has extremely useful text processing features, from the POSIX Extended or Perl regular expressions to parsing XML documents.

Spam is generally created by programs, like the Perl script that posted to 6, 000 Usenet groups for Canter & Siegel.

The code for this module will be a simple layer on top of LWP: : UserAgent, which is included in the libwww-perl package.

So I assume that it's possible to run Perl CGI scripts with this server.

XML: : Simple converts XML input files into an easily manipulated Perl data structure, and writes such data structures back out as XML.

XML: : Simple provides an intuitive, pure-Perl parser for simple XML files, and the SAX API is supported by most of the parsing modules.

Perl and the PHP kind may retrieve the code description, and automatically produces the HTML code choice element with the user language.

Packages and modules are important to any Perl programmer.

As the assistant, I completed the access and storage of the Blog data by using C language and Perl database.

Furthermore, the Perl 6 regular expressions can be, but don't have to be, radically different from their Perl 5 counterparts.

The type perl command reveals how the perl command is interpreted on the command line.

Documentation can be embedded inside Perl programs with the POD format.

Like Perl and Python, it's an open source, agile programming language that offers full support for object-oriented programming.

Awk is commonly used for basic tasks such as breaking up text into fields; Perl excels at text manipulation by design.

Listing 2 demonstrates a simple Perl program that establishes connection to the database SAMPLE and returns today's date.

For custom protocols and data structures, you can use Perl to extract the raw data and get all the information you need.

You don't have to revolutionize your thinking (or coding! ) to get increased clarity with Perl.

For this reason I tend not to suffix my Perl applications with any special endings.

The syntax for patterns used in these functions closely resembles Perl.

After reading this chapter, I understood the syntax and features of Perl 6 much better than before.

pl program is detailed in " Create geographical plots of your data using Perl, GD, and plot-latlong. "

A developer with some Perl experience already probably has some experience working with regular expressions, too.

Perl array is always one-dimension.

The language for doing a regular expression is not Perl; it is a domain-specific language that Perl happens to have a hook into.

Like Perl, REBOL, REXX, and TCL, it's a flexible scripting language with powerful text manipulation capabilities.

In this article, we explain the most common portability pitfalls and present a roadmap for migrating Perl scripts from Solaris to Linux.

In contrast with other open source languages like Perl and Python, PHP lacks a robust community effort to develop a math library.

This would have the dual benefit of being pretty tough to forge, while remaining portable to mod_perl-based scripts.

The reason is that Perl does little more with a module than importing the text and running it through the same compilation stage.

A dictionary in Vimscript is essentially the same as an AWK associative array, a Perl hash, or a Python dictionary.

Chances are that you will notice the same thing when you first think about porting legacy, untested, Perl to Python.

This tells Perl to use the Equation module, equation, and to look for Equation. pm in the current directory.

Apache uses Perl Compatible Regular Expressions provided by the PCRE library.

As long as the Earth's magnetic field is aligned correctly, this will solve every Perl problem you may encounter.

This isn't strictly true; it's possible with Perl, bash, and several other languages to insert delays to automate passwords.

We use the Java programming language (someone on the team suggested using Perl and had to be escorted from the room under heavy security).

pkill -HUP inetd will do in one concise command as much as a Perl script four or more lines long.

Designed to deliver to Perl the ability to compactly store and speedily manipulate large N-dimensional data arrays.

VECT provides a unified graphical user interface for data extraction, data conversion, output composition, and Perl code generation.

Has all the Perl modules you could ever want.

Any Perl object requires the new and DESTROY methods to be defined.

In fact, Inline is probably going to be the default interface method in Perl 6. It's that good.

It defines a C-language function to do the expected action, and then it treats it as a Perl function thereafter.