For your first example, this type of command line argument parsing can be carried out more simply with the -s switch to the Perl executable - This argument enables rudimentary switch parsing on the command line after the script name but before any filename arguments (or before a --). Any switch found is removed from @ARGV and a variable with a corresponding name is set.

For example, the following code will print bar! if the command line switch -foo is passed to the script:

#!/usr/bin/perl -s

print "bar!\n" if ($foo);

[download]

This behaviour is documented in perlrun - For a truly evil use of this behaviour (and Perl in general) have a look at theDamian's selfGOL obfuscation :-)

 

perl -e 'print+unpack("N",pack("B32","00000000000000000000000111011111")),"\n"'

In reply to Re: Poor's man command line arguments by rob_au
in thread Poor's man command line arguments by zjunior

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