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#!/usr/bin/perl
# Create a script to demonstrate creating dynamic variable name,
# assign a value to the variable and finally print the variable.
# The variable name would be passed as command line argument.
use feature 'say';
die "Usage:\n\tperl ch-2.pl <variable name>\n\n" if @ARGV != 1;
die "Error: Only alphanumeric characters and underscore are allowed\n\n" if $ARGV[0]=~/\W+/;
# Not exactly what the task is asking for
# but it still demonstrates that a variable can be
# dynamically created
# The basic idea here is that if the variable can be referenced
# then the variable exists
# I used eval to basically do
# my $varname = \$<some_variable_name>; of course with out <>
# This would create a reference to a scalar value
my $varname = eval("\\\$" . $ARGV[0]);
# Changes to the reference...
$$varname = 0|100*rand;
# Should update the value of the variable being referred to
# the code below will print the random generated value assigned
# to the reference.
say "You created a variable named \"$ARGV[0]\" and has a value of ${$ARGV[0]}\n";
say "This line prints the value of a variable named dynamic_var: [$dynamic_var]";
say "If the user inputs the same variable name, dynamic_var variable will have value otherwise it will be empty\n";
#NOTE: because of the nature of the task,
# use strict was removed.
=begin
perl .\ch-2.pl dynamic_var
You created a variable named "dynamic_var" and has a value of 78
This line prints the value of a variable named dynamic_var: [78]
If the user inputs the same variable name, dynamic_var variable will have value otherwise it will be empty
perl .\ch-2.pl my_var
You created a variable named "my_var" and has a value of 38
This line prints the value of a variable named dynamic_var: []
If the user inputs the same variable name, dynamic_var variable will have value otherwise it will be empty
=cut
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