![]() Lines starting with = are interpreted as the start of a section of embedded documentation (pod), and all subsequent lines until the next =cut are ignored by the compiler. Simply saying comments in Perl start with a hash symbol and run to the end of the line − For example, in the above program, a line starting with hash # is a comment. #Perl print codeComments can be used to make program user friendly and they are simply skipped by the interpreter without impacting the code functionality. Comments in PerlĬomments in any programming language are friends of developers. Use an underscore (_) in places of spaces. #Perl print PcThe output I get from this command on my Windows PC looks like this: C:/Perl/lib C:/Perl/site/lib. File names can contain numbers, symbols, and letters but must not contain a space. Here's a simple way to print your Perl include path from the command line: perl -e 'print qq (INC)' You can just run that command from the Unix/Linux or DOS command line. PL file extension in order to be recognized as a functioning Perl script. There are many programs designd for programmers available for download on the web.Īs a Perl convention, a Perl file must be saved with a. There are several programs available for every type of platform. Following two statements produce the same result.Ī Perl script can be created inside of any normal simple-text editor program. They are only required occasionally to clarify the issues of precedence. You can use parentheses for functions arguments or omit them according to your personal taste. Before you execute your script, be sure to change the mode of the script file and give execution priviledge, generally a setting of 0755 works perfectly and finally you execute the above script as follows − Here /usr/bin/perl is actual the perl interpreter binary. This execution will produce the following result −Īssuming you are already on $ prompt, let's open a text file using vi or vim editor and put the following lines inside your file. Let's try something at $ prompt as follows − You can use Perl interpreter with -e option at command line, which lets you execute Perl statements from the command line. First Perl Program Interactive Mode Programming Whitespace serves mostly to separate tokens, unlike languages like Python where it is an important part of the syntax, or Fortran where it is immaterial. Perl is a free-form language: you can format and indent it however you like. Every simple statement must end with a semicolon ( ). Loops, subroutines, and other control structures allow you to jump around within the code. This chapter is designd to quickly get you up to speed on the syntax that is expected in Perl.Ī Perl program consists of a sequence of declarations and statements, which run from the top to the bottom. However, there are some definite differences between the languages. Perl borrows syntax and concepts from many languages: awk, sed, C, Bourne Shell, Smalltalk, Lisp and even English. ![]()
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