Introduction to Perl
Perl, a feature-rich computer programming language that runs on more than 100 computer platforms for a wide range of applications, from mainframe to portable devices, from rapid prototyping to large-scale scalable development.
The Perl language is used in a wide range of applications. In addition to CGI, Perl is used in graphics programming, systems management, network programming, finance, biology, and other fields. Because of its flexibility, Perl is known as the Swiss Army Knife in scripting languages.
What is Perl?
Perl is a programming language designed by Larry Wall and constantly updated and maintained by him.
Perl has the power and flexibility of a high-level language such as C. In fact, you will see that many of its features are borrowed from the C language.
Perl is like a scripting language. Perl doesn't require compilers and linkers to run code. All you have to do is write the program and tell Perl to run it. This means that Perl is ideal for quick solutions to small programming problems and for prototyping large events to test potential solutions.
Perl provides all the features of scripting languages such as sed and awk, as well as many of the features they don't have. Perl also supports sed to Perl and awk to Perl translators.
In short, Perl is as powerful as C, as easy as scripting languages such as awk and sed.
- Compared to the "advanced" language of C and Pascal, the Perl language directly provides more convenient programming elements such as generic variables, dynamic arrays, and hash tables.
- Perl has the powerful and flexible features of dynamic languages, and also borrows grammar rules from C/C++, Basic, Pascal and other languages to provide a lot of redundant syntax.
- Perl does better than other high-level languages (like Python) in terms of uniform variable types and masking details.
- Because of the grammar borrowed from other languages, programmers who switch from other programming languages to Perl can quickly write and complete tasks, making the Perl language an easy-to-use language.
It is also because of Perl's flexibility and "excessive" redundant syntax that it has gained a "write-only" reputation because Perl programs can be written very casually (for example, variables can be declared without declaration). Use it directly, but you may get less results by writing fewer letters (without giving an error). The code of many Perl programs is hard to read, and the length of the program code that implements the same function can be ten times different, which makes the program The maintainers (even writers) are difficult to maintain.
Similarly, because of the random nature of Perl, it may cause some Perl programmers to forget the grammar, so that they have to check the Perl manual frequently.
The suggested workaround is to use use strict; and use warnings; in the program, and to harmonize the code style, using the library instead of using "hard code". Perl can also write code as elegant as languages like Python or Ruby.
A lot of times, the perl.exe process takes up a lot of memory space, although it is only a moment, but it feels bad.