Perl (Scripting) articles

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Arrays Append element to the beginning of an array (unshift) Append element to the end of an array (push) Count elements in an array Create array over SSH Duplicate elements in an array Getting Started with Arrays Print last value in an array in Perl Remove all elements from array (undef) Remove duplicate values from an array Remove element beginning of array (shift) Remove element from array (splice) Remove empty lines from array Remove first element from array (splice) Remove last element from an array (pop) Replace element in array (map) Sort array Store files directories in array (glob) Booleans Getting Started with Booleans Built in Perl commands %ENV environment special hash Escape special characters using quotemeta (\Q \E) eval function Lower case (lc) Random number generator (rand) scriptname $0 Update the first character in a string to be upper case (ucfirst) Upper case (uc) Variable contains (=~) or does not contain (!~) Wrap text (Text::Wrap) Command Line Options and Flags Getting Started with command line options and flags Count Count characters in a string (length) Count lines in a file ($.) Data::Dumper Getting Started with Data::Dumper Date Time Add or subtract time using Time::Piece and Time::Seconds (timepiece) Date and time using localtime Date and time using strftime Date and Time using Time::Piece (timepiece) epoch date and time Directories List directories Email Net::SMTP (email) Send email using Email::Sender and Email::MIME File::Basename File and Directory basename and dirname File::Touch Getting Started with File::Touch Files Previous, current, and next line in a file (seek, tell) Transfer a file Files - TXT / DOC / CSV Determine if file contains a string of data Open file for reading (<) Open file for writing appending overwriting (> and >>) Read and write to the same file Replace values in a file Files - XLS Append or replace data in an Excel spreadsheet (Spreadsheet::ParseExcel) Read an Excel 95-2003 spreadsheet (xls) Write to an Excel 95-2003 spreadsheet (xls) Hash Append key value pairs to a hash Append values to a hash Count keys and values in a hash Define a hash Delete a key in a hash Determine if a hash is defined Determine if a key is defined in a hash Lock keys and values in a hash Loop through keys in a hash Loop through values in a hash Match keys in a hash using grep Print values in a regular hash Remove value from a key in a hash Sort keys in a hash Hash (with array) Append key value pairs to a hash that contains an array Append keys to a hash that contains an array Append values to a hash that contains an array Count keys in a hash that contains an array Count values in a hash that contains an array Define a hash that contains an array Define hash that contains an array Determine if an array in a hash is defined Determine if an array in a hash is empty Loop through key value pairs in an array in a hash Loop through keys in an array in a hash Loop through values in an array in a hash Remove all elements from an array in a hash Remove values from an array in a hash Hash Reference Append values to a reference hash Append values to a reference hash that contains an array Define a reference hash Determine if a key is defined in a reference hash Determine if a reference hash is defined Print values in a reference hash if elsif else statements Determine if a directory is empty Getting Started with if elsif else statements if file contains match get next line Install Install Perl on Linux JSON Getting Started with JSON::Create Getting Started with JSON::Parse JSON Modification of a read-only value JSON::Parse reason Not Found error Object Not Found Lists Count the number of elments in an list Logger Getting Started with Log::Log4perl Logger Loops Break out of a loop foreach loops Loop through a file until line match loop through a range of items in an array Moving onto next value in a loop (next) while loop Math Addition and Increment (+) Convert base 16 hexadecimal to decimal Division (/) Multiplication (*) Subtraction (-) Sum of integers in a file Modules Create your own module Determine if a module is installed Install a module using cpan Install a module using cpanm Native operating system commands Native operating system command using `backticks` or system Other Prompt a user for input (stdin) Scientific notation with Microsoft Excel Packages Getting Started with Packages Printing output Bold text (Term::ANSIColor) Display text on the console (print and say) Regular Expressions (regex) ( and ) characters Append leading zeros to numbers carriage returns (\r ^M) Dealing with Microsoft Word curly fancy smart quotes Do something beginning of line (^) Do something end of line ($) Do something every nth line in a file Do something range of lines Escape literal dollar sign $ Flatten lists (merge similar lines) match first all last occurrence of a pattern Match last occurrence of a line in a file new lines \n and carriage returns \r Regular expression delimiter Replace text in a file (-pi -e =~) Trailing forward slash Using grep whitespace (\s) REST API (curl) basic authentication username password with the LWP::UserAgent REST API module curl HTTPS (LWP::UserAgent, LWP::Protocol::https) GET request with the LWP::UserAgent REST API module Getting Started with the LWP::UserAgent REST API module headers with the LWP::UserAgent REST API module insecure SSL certificates with the LWP::UserAgent REST API module POST data with the LWP::UserAgent REST API module Return Break out of a subroutine (return) return a hash return a string return an array return one or more variables Return Code Return Code using system SFTP Getting Started with Net::SFTP Spliting string Cut a string into pieces (substr) Split fields at delimiter SQL database Connect to a SQL database SSH Getting Started with Net::OpenSSH Getting Started with Net::SSH::Perl Local and remote variables over SSH Public key authentication with Net::SSH::Perl Subroutines Getting Started with Subroutines Identical subroutine names (package, namespace) Pass values to a subroutine (@_ and $_ and shift) Troubleshooting Global symbol requires explicit package name Resolve "Can't locate Example.pm in @INC" in Perl Resolve "Host key for has changed" Resolve "JSON Error Empty input parsing initial state" Resolve "Reference found where even-sized list expected" Resolve "Variable will not stay shared" Variables / Scalars Append values to a variable (.=) Determine if a variable is defined Determine if a variable is empty or null Getting Started with scalars and variables Global and lexical variables (my and our) Replace values in a variable (=~) wkplc.properties file Define the Portal Context Root (WpsContextRoot) in Workplace Properties file (wkplc.properties) XML::Simple Data::Dumper and XML::Simple Getting Started with XML::Simple XML::Simple Arrays XML::Simple ForceArray XML::Simple Ignore Attributes XML::Simple looping through hash keys XML::Simple looping through keys XML::Simple looping through keys that contain attributes XML::Simple output XML (XMLout) XML::Simple Printing Attributes XML::Simple printing keys (XMLin) XML::Simple printing values (XMLin) XML::Simple store XML in a variable (XMLin) XML::Twig XML::Twig change tag (set_tag) XML::Twig change value (set_text) XML::Twig loop through tags (first_child children) XML::Twig output to a file XML::Twig parse XML XML::Twig print attributes XML::Twig print values (text)