- Getting Started<\/li>
- Hello World<\/li>
- Variables<\/li>
- Loops and Ifs<\/li>
- Functions<\/li><\/ol>\n\n\n\n
Getting Started:-<\/strong><\/h4>\n\n\n\n
You’ll need the Perl interpreter to get started with Perl. There’s a 99.99 percent chance it’s already installed on any UNIX computer. You must download and install the most recent version of the language on your Windows or Mac laptop. (For further information, see the links at the end of this page.) Perl is a free programming language that is freely available on the Internet.<\/p>\n\n\n\n
Next, check through the DOCS directory that comes with Perl; there should be user-manual-type material there. It wouldn’t hurt to go through or at least scan all of the documentation at some time. It will be inconvenient at first, but after reading this post, it will make a lot more sense.<\/p>\n\n\n\n
Hello World<\/strong>:-<\/h4>\n\n\n\n
Once Perl is installed, double-check that your path is set to contain the Perl executable. Then, using a text editor, make a text file. Insert the following line into the file:<\/p>\n\n\n
print<\/span> \"Hello World!\\n\"<\/span>;\n\nName the file \"test1.pl\"<\/span>. At the command prompt, type:\n\nperl test1.pl<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nThe code in the text file will be run and executed by Perl. The phrase “Hello World!” should be printed to stdout (standard out). As you can see, writing and running programmes in Perl is a breeze. (If you’re using UNIX, you may add a comment like #! \/usr\/bin\/perl to the first line to avoid having to write “perl” at the command line.)<\/p>\n\n\n\n
The print command sends information to stdout. A line feed is indicated by the n notation. If you changed the test programme to look like this (# marks a remark), it would be clearer:<\/p>\n\n\n
# Print on two lines<\/span>\n print<\/span> \"Hello\\nWorld!\\n\"<\/span>;<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nIt’s worth noting that the print command recognized the “n” as a line feed rather than the actual letters. The usage of double quotes, rather than the print command, caused the misinterpretation (a practise called quoting in Perl). Instead of double quotations, you might use single quotes, like in:<\/p>\n\n\n
print<\/span> 'Hello\\nWorld!\\n'<\/span>;<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nVariables<\/strong>:-<\/h4>\n\n\n\n
In Perl, variables are fascinating. You don’t declare them, and you constantly refer to them with a $. They are created when they are first used. Consider the following scenario:<\/p>\n\n\n
$s = \"Hello\\nWorld\\n\"<\/span>;\n $t = 'Hello\\nWorld\\n'<\/span>;\n print<\/span> $s, \"\\n\"<\/span>, $t;<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n$i = 5<\/span>;\n $j = $i + 5<\/span>;\n print<\/span> $i, \"\\t\"<\/span>, $i + 1<\/span>, \"\\t\"<\/span>, $j; # \\t = tab<\/span><\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n$a = \"Hello \"<\/span>;\n $b = \"World\\n\"<\/span>;\n $c = $a . $b; # note use of . to concat strings<\/span>\n print<\/span> $c;<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nLoops and Ifs<\/strong>:-<\/h4>\n\n\n\n
You may make a basic for loop in the same way you would in C:<\/p>\n\n\n
for<\/span> ($i = 0<\/span>; $i < 10<\/span>; $i++)\n {\n print<\/span> $i, \"\\n\"<\/span>;\n }<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nWhile <\/strong>statements are simple:<\/p>\n\n\n
$i = 0<\/span>;\n while<\/span> ( $i < 10<\/span> )\n {\n print<\/span> $i, \"\\n\"<\/span>;\n $i++;\n }<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nIf<\/strong> statements are similarly simple:<\/p>\n\n\n
for<\/span> ($i = 0<\/span>; $i < 10<\/span>; $i++)\n {\n if<\/span> ($i != 5<\/span>)\n {\n print<\/span> $i, \"\\n\"<\/span>;\n }\n }<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nFunctions:- <\/h4>\n\n\n\n
The term sub is used to construct a subroutine. The procedure receives all variables in an array named . As a result, the following code is valid:<\/p>\n\n\n
show ('cat'<\/span>, 'dog'<\/span>, 'eel'<\/span>);\r\n\r\n sub show\r\n {\r\n for<\/span> ($i = 0<\/span>; $i <= $#_; $i++)<\/span>\r\n {\r\n print<\/span> $_[$i], \"\\n\"<\/span>;\r\n }\r\n }<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nRemember that $# returns the array’s greatest index (the number of elements minus 1), thus $# equals the number of arguments minus 1. If you enjoy that kind of obscurity, you’ll enjoy PERL.<\/p>\n\n\n\n
The term local can be used to define local variables in a subroutine, as in:<\/p>\n\n\n
sub xxx\r\n {\r\n local ($a, $b, $c)\r\n ...\r\n }<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\nYou may also use & to run a function, as in:<\/p>\n\n\n
&show ('a'<\/span>, 'b'<\/span>, 'c'<\/span>);<\/code><\/span>Code language:<\/span> JavaScript<\/span> (<\/span>javascript<\/span>)<\/span><\/small><\/pre>\n\n\nAlthough the & sign is only necessary when there is uncertainty, some programmers use it frequently.<\/p>\n\n\n\n
The keyword return is used to return a value from a procedure.<\/p>\n\n\n\n
Although the & sign is only necessary when there is uncertainty, some programmers use it frequently.<\/p>\n\n\n\n
The keyword return is used to return a value from a procedure.<\/p>\n\n\n\n
What are the features of Perl?<\/h2>\n\n\n\n
![\"Perl](\"https:\/\/slideplayer.com\/slide\/14953448\/91\/images\/5\/Perl+Features+Perl+takes+the+best+features+from+other+languages%2C+such+as+C%2C+awk%2C+sed%2C+sh%2C+and+BASIC%2C+among+others..jpg\")
<\/figure>\n\n\n\n- Perl pulls features from a variety of languages, including C, awk, sed, sh, and BASIC.<\/li>
- Database integration interface in Perl Oracle, Sybase, Postgres, MySQL, and other third-party databases are supported by DBI.<\/li>
- Its Object-oriented programming syntax is relatively easy.<\/li>
- It may be readily expanded because to the 25,000 open source modules it supports. Unicode is supported.<\/li>
- Perl is a scripting language that may be extended. The Comprehensive Perl Archive Network has approximately 20,000 third-party modules accessible (CPAN).<\/li>
- It is capable of processing encrypted online data, including e-commerce transactions. It’s a platform-independent language. It comes with a regular expression engine that can alter any kind of text.<\/li>
- It may be integrated into other systems, such as web and database servers. It is GNU-licensed open source software. Perl is used in a lot of frameworks.<\/li><\/ul>\n\n\n\n
Video recommendation of Perl:- <\/h3>\n\n\n\n