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Tie::Scalar(3)
NAME
  Tie::Scalar, Tie::StdScalar - base class definitions for tied scalars

SYNOPSIS
      package NewScalar;
      require Tie::Scalar;

      @ISA = (Tie::Scalar);

      sub FETCH { ... }		  # Provide a needed method
      sub TIESCALAR { ... }	  # Overrides inherited method

      package NewStdScalar;
      require Tie::Scalar;

      @ISA = (Tie::StdScalar);

      # All methods provided by default, so define only what needs be overridden
      sub FETCH { ... }

      package main;

      tie $new_scalar, 'NewScalar';
      tie $new_std_scalar, 'NewStdScalar';

DESCRIPTION
  This module provides some skeletal methods for scalar-tying classes. See
  the perltie manpage for a list of the functions required in tying a scalar
  to a package. The basic Tie::Scalar package provides a "new" method, as
  well as methods "TIESCALAR", "FETCH" and "STORE". The Tie::StdScalar
  package provides all the methods specified in	 the perltie manpage. It
  inherits from Tie::Scalar and causes scalars tied to it to behave exactly
  like the built-in scalars, allowing for selective overloading of methods.
  The "new" method is provided as a means of grandfathering, for classes that
  forget to provide their own "TIESCALAR" method.

  For developers wishing to write their own tied-scalar classes, the methods
  are summarized below. The the perltie manpage section not only documents
  these, but has sample code as well:

  TIESCALAR classname, LIST
      The method invoked by the command "tie $scalar, classname". Associates
      a new scalar instance with the specified class. "LIST" would represent
      additional arguments (along the lines of the AnyDBM_File manpage and
      compatriots) needed to complete the association.

  FETCH this
      Retrieve the value of the tied scalar referenced by this.

  STORE this, value
      Store data value in the tied scalar referenced by this.

  DESTROY this
      Free the storage associated with the tied scalar referenced by this.
      This is rarely needed, as Perl manages its memory quite well. But the
      option exists, should a class wish to perform specific actions upon the
      destruction of an instance.

MORE INFORMATION
  The the perltie manpage section uses a good example of tying scalars by
  associating process IDs with priority.

Index for Section 3

Alphabetical listing for T

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