If-else statement

Perl IF...ELSE statement

A Perl if statement can be followed by an optional else statement, which executes when the boolean expression is false.

Syntax:

The syntax of an if...else statement in Perl programming language is:

if(boolean_expression){

   # statement(s) will execute if the given condition is true

}else{

   # statement(s) will execute if the given condition is false

}

If the boolean expression evaluates to true then the if block of code will be executed otherwise else block of code will be executed.

Example:

#!/usr/local/bin/perl

$a = 100;

# check the boolean condition using if statement

if( $a < 20 ){

    # if condition is true then print the following

    printf "a is less than 20\n";

}else{ 

    # if condition is false then print the following

    printf "a is greater than 20\n";

}

print "value of a is : $a\n";

$a = "";

# check the boolean condition using if statement

if( $a ){

    # if condition is true then print the following

    printf "a has a true value\n";

}else{

   # if condition is false then print the following

    printf "a has a false value\n";

}

print "value of a is : $a\n";

When the above code is executed, it produces following result:

a is greater than 20

value of a is : 100

a has a false value

value of a is :