Show me the code!
Perl is a programming language developed by Larry Wall, especially designed for text processing. Though Perl is not officially an acronym but many times it is used as it stands for “Practical Extraction and Report Language”. It runs on a variety of platforms, such as Windows, Mac OS, and the various versions of UNIX.
Perl functions don’t have parameters, their arguments are passed in an array @_. You can simulate parameters by assigning to a list, but you can also just apply the usual array operations to @_.
Control statements in Perl can also be written with the conditional following the statements (called “postfix”). This syntax functions (nearly) identically to the usual one you would expect.
Variables whose names begin with % are hashes, which are essentially arrays subscripted by strings. As with arrays, %sue is a hash, and it is a different variable from $sue, though members of %sue are selected by $sue{$s}.
Variables whose names begin with @ are arrays. If @sue is an array, it is different variable from $sue. However, members of @sue are selected by $sue[$i].
This is how you would display “Hello World” in Perl. It’s quite similar to Bash, but note the differences carefully!
Create a text file called hello_world.pl containing the following code:
#!/usr/bin/perl # # The traditional first program. # Strict and warnings are recommended. use strict; use warnings; # Print a message. print "Hello, World!\n";
Navigate to a directory where your hello_world.pl is located and make the file executable:
$ chmod +x hello_world.pl
Now you are ready to execute your first perl script:
./hello_world.pl