Better Automation of Perl Execution

• One of the standard Perl command line options is the -w switch. The purpose of this switch is to turn on Perls diagnostic mode. This mode reports errors in a longer and more readable format. You should always use it when developing Perl programs.
• To use the -w switch (and you always should when developing code), just add it to the comment line (that is not really a comment line) at the top of your program.
• Also, at the beginning of your program, use the use strict; instruction. This tells Perl to tell you when you are doing something dangerous.
• Did I mention that you should always use the -w switch to develop your code?
• Did I mention that you should always use the use strict; command to develop your code?
• Really. I mean it. You will thank me for this someday... honest.

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• Unix Example:
  

   
  $ # Note the first line has changed to include -w
  $ cat helloworld.perl
  #!/usr/bin/perl -w
  use strict;
  print "Hello World\n";
  $ # Now give it execute permission (only necessary once)
  $ chmod +x helloworld.perl
  $ # Now lets run it and get a look at the output
  $ ./helloworld.perl
  Hello World