Mohd Mohtashim has Published 251 Articles

Checking for Key/Value Existence in Perl Hash

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:52:55

390 Views

If you try to access a key/value pair from a hash in Perl that doesn't exist, you'll normally get the undefined value, and if you have warnings switched on, then you'll get a warning generated at run time. You can get around this by using the exists function, which returns ... Read More

Extracting Keys and Values from Hash in Perl

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:45:18

2K+ Views

You can get a list of all of the keys from a hash in Perl by using keys function, which has the following syntax −keys %HASHThis function returns an array of all the keys of the named hash. Following is the example −Example Live Demo#!/usr/bin/perl %data = ('John Paul' => 45, ... Read More

Accessing Hash Elements in Perl

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:42:13

254 Views

When accessing individual elements from a hash in Perl, you must prefix the variable with a dollar sign ($) and then append the element key within curly brackets after the name of the variable. For example −Example Live Demo#!/usr/bin/perl %data = ('John Paul' => 45, 'Lisa' => 30, 'Kumar' => 40); ... Read More

Creating Hashes in Perl

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:40:16

125 Views

Perl Hashes are created in one of the two following ways. In the first method, you assign a value to a named key on a one-by-one basis −$data{'John Paul'} = 45; $data{'Lisa'} = 30; $data{'Kumar'} = 40;In the second case, you use a list, which is converted by taking individual ... Read More

Selecting Elements from Lists in Perl

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:31:38

365 Views

The list notation in Perl is identical to that for arrays. You can extract an element from an array by appending square brackets to the list and giving one or more indices −Example Live Demo#!/usr/bin/perl $var = (5, 4, 3, 2, 1)[4]; print "value of var = $var"OutputThis will produce the ... Read More

Merging Arrays in Perl

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:27:58

1K+ Views

Because an array in Perl is just a comma-separated sequence of values, you can combine them together as shown below −Example Live Demo#!/usr/bin/perl @numbers = (1, 3, (4, 5, 6)); print "numbers = @numbers";OutputThis will produce the following result −numbers = 1 3 4 5 6The embedded arrays just become a ... Read More

The $[ Special Variable in Perl

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:13:56

246 Views

Perl provides numerous special variables, which have their predefined meaning.We have a special variable, which is written as $[. This special variable is a scalar containing the first index of all arrays. Because Perl arrays have zero-based indexing, $[ will almost always be 0. But if you set $[ to ... Read More

Sorting Arrays in Perl

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:11:45

572 Views

The sort() function in Perl sorts each element of an array according to the ASCII Numeric standards. This function has the following syntax −Syntaxsort [ SUBROUTINE ] LISTThis function sorts the LIST and returns the sorted array value. If SUBROUTINE is specified then specified logic inside the SUBROUTINE is applied ... Read More

Transform Perl Arrays to Strings

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:09:28

6K+ Views

We can use the join() function in Perl to rejoin the array elements and form one long scalar string. This function has the following syntax −Syntaxjoin EXPR, LISTThis function joins the separate strings of LIST into a single string with fields separated by the value of EXPR and returns the ... Read More

Transform Perl Strings into Arrays

Mohd Mohtashim

Mohd Mohtashim

Updated on 29-Nov-2019 05:07:22

2K+ Views

Let's look into a Perl function called split(), which has the following syntax −Syntaxsplit [ PATTERN [ , EXPR [ , LIMIT ] ] ]This function splits a string into an array of strings and returns it. If LIMIT is specified, splits into at most that number of fields. If ... Read More

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