Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Programming Scripts Articles
Page 32 of 33
Perl Equality Operators
These are also called relational operators in Perl. Assume variable $a holds 10 and variable $b holds 20 then, let's check the following numeric equality operators available in Perl −Sr.No.Operator & Description1== (equal to)Checks if the value of two operands are equal or not, if yes then condition becomes true.Example− ($a == $b) is not true.2!= (not equal to)Checks if the value of two operands are equal or not, if values are not equal then the condition becomes true.Example− ($a != $b) is true.3Checks if the value of two operands are equal or not, and returns -1, 0, or 1 ...
Read MoreThe Infinite Loop in Perl
A loop becomes an infinite loop if a condition never becomes false. The for loop is traditionally used for this purpose. Since none of the three expressions that form the loop are required, in Perl, you can make an endless loop by leaving the conditional expression empty.#!/usr/local/bin/perl for( ; ; ) { printf "This loop will run forever."; }You can terminate the above infinite loop by pressing the Ctrl + C keys.When the conditional expression is absent, it is assumed to be true. You may have an initialization and increment expression, but as a programmer more commonly use the ...
Read MoreLoop Control Statements in Perl
Loop control statements change the execution from its normal sequence. When execution leaves a scope, all automatic objects that were created in that scope are destroyed.Perl supports the following control statements. Click the following links to check their detail.Sr.No.Control Statement & Description1next statementIt causes the loop to skip the remainder of its body and immediately retest its condition prior to reiterating.2last statementTerminates the loop statement and transfers execution to the statement immediately following the loop.3continue statementA continue BLOCK, it is always executed just before the conditional is about to be evaluated again.4redo statementThe redo command restarts the loop block without ...
Read MoreCreating Hashes in Perl
Perl Hashes are created in one of the two following ways. In the first method, you assign a value to a named key on a one-by-one basis −$data{'John Paul'} = 45; $data{'Lisa'} = 30; $data{'Kumar'} = 40;In the second case, you use a list, which is converted by taking individual pairs from the list: the first element of the pair is used as the key, and the second, as the value. For example −%data = ('John Paul', 45, 'Lisa', 30, 'Kumar', 40);For clarity, you can use => as an alias for, to indicate the key/value pairs as follows −%data = ...
Read MoreHow to create Array in Perl?
Perl Array variables are prefixed with the @ sign and are populated using either parentheses or the qw operator. For example −@array = (1, 2, 'Hello'); @array = qw/This is an array/;The second line uses the qw// operator, which returns a list of strings, separating the delimited string by white space. In this example, this leads to a four-element array; the first element is 'this' and last (fourth) is 'array'. This means that you can use different lines as follows −@days = qw/Monday Tuesday ... Sunday/;You can also populate an array by assigning each value individually as follows −$array[0] = 'Monday'; ... $array[6] = 'Sunday';
Read MoreCreating Variables in Perl
Perl variables do not have to be explicitly declared to reserve memory space. The declaration happens automatically when you assign a value to a variable. The equal sign (=) is used to assign values to variables.Keep a note that this is mandatory to declare a variable before we use it if we use strict statement in our program.The operand to the left of the = operator is the name of the variable, and the operand to the right of the = operator is the value stored in the variable. For example −$age = 25; ...
Read MoreWhat are Perl Numerical Literals?
Perl stores all the numbers internally as either signed integers or double-precision floating-point values. Numeric literals are specified in any of the following floating-point or integer formats −TypeValueInteger1234Negative integer-100Floating point2000Scientific notation16.12E14Hexadecimal0xffffOctal0577
Read MoreWhat are different Perl Data Types?
Perl is a loosely typed language and there is no need to specify a type for your data while using it in your program. The Perl interpreter will choose the type based on the context of the data itself.Perl has three basic data types: scalars, arrays of scalars, and hashes of scalars, also known as associative arrays. Here is a little detail about these data types.Sr.No.Types & Description1ScalarScalars are simple variables. They are preceded by a dollar sign ($). A scalar is either a number, a string, or a reference. A reference is actually an address of a variable, which ...
Read MoreWhat is Perl Identifiers?
Perl borrows syntax and concepts from many languages: awk, sed, C, Bourne Shell, Smalltalk, Lisp, and even English. However, there are some definite differences between the languages. This chapter is designed to quickly get you up to speed on the syntax that is expected in Perl.A Perl program consists of a sequence of declarations and statements, which run from the top to the bottom. Loops, subroutines, and other control structures allow you to jump around within the code. Every simple statement must end with a semicolon (;).A Perl identifier is a name used to identify a variable, function, class, module, ...
Read MorePerl File Extension
Perl is a general-purpose programming language originally developed for text manipulation and now used for a wide range of tasks including system administration, web development, network programming, GUI development, and more.A Perl script can be created inside of any normal simple-text editor program. There are several programs available for every type of platform. There are many programs designed for programmers available for download on the web.As a Perl convention, a Perl file must be saved with a .pl or.PL file extension in order to be recognized as a functioning Perl script. File names can contain numbers, symbols, and letters but ...
Read More