For Loop in Perl

FOR Loop Syntax in Perl:

Syntax: 
for (initialization; test; re-initialization) BLOCK


#!/usr/bin/perl

use strict;
use warnings;

print "\nStart For Loop"; 

for ($count = 1; $count <= 5; $count++) {
  print "\nEach Element : " . $count;
}
print "\nEnd For Loop"; 

O/P:

Start For Loop
Each Element : 1
Each Element : 2
Each Element : 3
Each Element : 4
Each Element : 5
End For Loop

Unix For Loop

#]mkdir for_test_dir1

#]mkdir for_test_dir2

#]mkdir for_test_dir3

#]cat for_test_dir1/for_test.txt
content 1
content 1
content 1

#]cat for_test_dir2/for_test.txt
content 2
content 2
content 2

#]cat for_test_dir3/for_test.txt
content 3
content 3
content 3
...
...

#] ls
for_test_dir1 for_test_dir2 for_test_dir3 for_test_dir4 for_test_dir5
......
......


#]foreach var (`ls`)
foreach? ls -ltr $var/for_test*
foreach? end

O/P:
It will list all the for_test files present in for_test_dir's

While loop in Perl

We can loop through For/Foreach/While in Perl.

We can discuss while loop now with the following example.

use strict;
use warnings;
use Data::Dumper;

my @names = ("Mother Teresa", "Abraham Lincoln", "Winston Churchill", "Mahathma Gandhi");

print "\n Looping While using counter";

my $i=0;

print "\n Scalar Array Size " . scalar(@names) . "\n";

while ($i <= $#names) {
   print "\n Looping ... " . $names[$i] . "\n";
   $i++;
}

print "\n";
  

Output :

 Looping While using counter
 Scalar Array Size 4

 Looping ... Mother Teresa

 Looping ... Abraham Lincoln

 Looping ... Winston Churchill

 Looping ... Mahathma Gandhi
 

Please refer to other topics in Perl like :
How to read command line arguments in Perl
How to pass command line arguments to perl script
Loop through Directory and read the files in Perl
How to create excel report in Perl

Please refer to other topics on Unix like :
Unix Delete Duplicated Lines in a File
Unix Unique Lines in a File
Unix Grep Examples
Unix Cut Command Examples
Search a Directory in Unix
Unix For Loop
pushd & popd in Unix
Find Size of Directory
Word Count

Please refer to other topics on AWK like :
Awk Examples
Print First Two Columns of File
Print Last Two Columns of File

Please refer to other topics on Dict like :
Dict in Python
Dict keys and values in Python

Please refer to other topics on List like :
List in Python
Append to list in Python
Delete the last name from the list in Python
Remove an element from List in Python
Check an element exists in an list in Python
Python Filter Vs Map Vs List Comprehension

Please refer to other topics on File Concepts like :
Print File Content in Python
Print File in Reverse Order in Python

Please refer to Regular Expressions Concepts :
Brief on Regular Expressions
Greedy Operators in Regular Expressions in Perl
Modifiers in Regular Expressions in Perl
Capturing concept in Regular Expressions in Perl
Capture Pre Match ,Post Match, Exact match in Regular Expressions in Perl
Non Capturing Paranthesis in Regular Expressions in Perl
Substitute nth occurance in Regular Expressions in Perl
All Topics in Regular Expressions in Perl

You might also wish to read other topics on Python like :
Python Class and Object Example
Inheritance in Python
Packages in Python
Exceptions in Python
How to remove duplicate lines from a file in Perl
How to remove duplicate lines from a file in Pyhton