#!/usr/bin/env perl

use strict;
use warnings;
use Getopt::Declare;

my $shell_cmds = <<'EOCMDS';
Commands: [repeatable]

	echo [-n] <words:/.*/>	ECHO WITHOUT NEWLINE 
			{ print $words; print "\n" unless $_PUNCT_{'-n'}; }

	[pvtype: chwho /u?g?a?/]
	[pvtype: chwhat /r?w?x?/]

	chmod [-R] <who:chwho>=<what:chwhat> <files>...	
				CHANGE FILE PERMISSIONS 
			{ foreach (@files) { print "chmod $who=$what $_\n"; } }

	help			SHOW THIS SUMMARY 
			{ $self->usage() }

	exit			EXIT SHELL 
			{ exit }

	<error:/.*/>	 
			{ print "Unknown command: $error\n";
			  print "(Try the 'help' command?)\n"; }
EOCMDS

my $shell = Getopt::Declare->new($shell_cmds,[-BUILD]);

my $count = 1;
sub prompt { print "$count> "; $count++; return <STDIN> }

print "Welcome to an interactive shell!\n";
$shell->parse(\&prompt);