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Top Forums UNIX for Dummies Questions & Answers question Post 70644 by google on Monday 2nd of May 2005 07:51:20 PM

05-02-2005

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$ - has a few meanings depending upon what it is you are looking at (shell program, awk program, sed, perl, etc).

In a shell program, $ is used to access the value of a variable. For example: Given the assignment, FOO=BAR. In a shell program, to access the value of FOO, you would type $FOO. If you were to type on the command line FOO=BAR and then, after hitting enter, type echo $FOO you would see the result, BAR.

In awk and sed (regular expressions in general), the $ symbol is used to denote the end of a line.

However, in Perl, the $ symbol is used to denote a variable (sort of the reverse of a shell program).

The >& business is a redirection method used when dealing with file descriptors. Standard File descriptors are 0 (STDIN), 1 (STDOUT), and 2 (STDERR). You can create your own file descriptors if you so choose. The >& is the syntax for redirecting the file descriptor stream

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perl::critic::policy::subroutines::protectprivatesubs

Perl::Critic::Policy::Subroutines::ProtectPrivateSubs(3pUser Contributed Perl DocumentatPerl::Critic::Policy::Subroutines::ProtectPrivateSubs(3pm)

NAME

       Perl::Critic::Policy::Subroutines::ProtectPrivateSubs - Prevent access to private subs in other packages.

AFFILIATION

       This Policy is part of the core Perl::Critic distribution.

DESCRIPTION

       By convention Perl authors (like authors in many other languages) indicate private methods and variables by inserting a leading underscore
       before the identifier.  This policy catches attempts to access private variables from outside the package itself.

       The subroutines in the POSIX package which begin with an underscore (e.g. "POSIX::_POSIX_ARG_MAX") are not flagged as errors by this
       policy.

CONFIGURATION

       You can define what a private subroutine name looks like by specifying a regular expression for the "private_name_regex" option in your
       .perlcriticrc:

	   [Subroutines::ProtectPrivateSubs]
	   private_name_regex = _(?!_)w+

       The above example is a way of saying that subroutines that start with a double underscore are not considered to be private.  (Perl::Critic,
       in its implementation, uses leading double underscores to indicate a distribution-private subroutine-- one that is allowed to be invoked by
       other Perl::Critic modules, but not by anything outside of Perl::Critic.)

       You can configure additional subroutines to accept by specifying them in a space-delimited list to the "allow" option:

	   [Subroutines::ProtectPrivateSubs]
	   allow = FOO::_bar FOO::_baz

       These are added to the default list of exemptions from this policy.  Allowing a subroutine also allows the corresponding method call. So
       "FOO::_bar" in the above example allows both "FOO::_bar()" and "FOO->_bar()".

HISTORY

       This policy is inspired by a similar test in B::Lint.

BUGS

       Doesn't forbid "$pkg->_foo()" because it can't tell the difference between that and "$self->_foo()".

SEE ALSO

       Perl::Critic::Policy::Variables::ProtectPrivateVars

AUTHOR

       Chris Dolan <cdolan@cpan.org>

COPYRIGHT

       Copyright (c) 2006-2011 Chris Dolan.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.  The full text of this license
       can be found in the LICENSE file included with this module.

perl v5.14.2							    2012-06-07		Perl::Critic::Policy::Subroutines::ProtectPrivateSubs(3pm)