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One Liners
Perl allows a complete, single line script to be run from the command line. These 'one liners' can be a quick way of making changes, finding information or presenting file content.

Most Perl programmers don't use one liners and are happy to use more relaxed, readable code in standard multi-line script files. Other programmers enjoy the speed and convenience of one liners or simply enjoy the challenge of cramming as much code/logic into one line as possible.

The following three sections provide information on how to create one liners, over 75 scripts, and detailed explanation of how the scripts work.

One Liner Basics Just the Scripts More Detailed Script Explanation

The other sections will provide much greater detail but here are two one liners to get your started. The first is very simple, a standard Hello World! script. Simply type this in at the command line to see the result.

The second is a bit more complicated, but does a find and replace of text in several files (in this example, replacing 'cat' with 'dog').

     perl -e " print 'Hello World!' "
     perl -i.bak -pe "s/cat/dog/g" input1.txt input2.txt input3.txt

That's it - complete Perl scripts on a single line of text!

If you have any suggestions or corrections, please let me know.