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UNIVERSAL(3)
NAME
  UNIVERSAL - base class for ALL classes (blessed references)

SYNOPSIS
      $io = $fd->isa("IO::Handle");
      $sub = $obj->can('print');

      $yes = UNIVERSAL::isa($ref, "HASH");

DESCRIPTION
  "UNIVERSAL" is the base class which all bless references will inherit from,
  see the perlobj manpage

  "UNIVERSAL" provides the following methods

  isa ( TYPE )
      "isa" returns true if "REF" is blessed into package "TYPE" or inherits
      from package "TYPE".

      "isa" can be called as either a static or object method call.

  can ( METHOD )
      "can" checks if the object has a method called "METHOD". If it does
      then a reference to the sub is returned. If it does not then undef is
      returned.

      "can" can be called as either a static or object method call.

  VERSION ( [ REQUIRE ] )
      "VERSION" will return the value of the variable "$VERSION" in the
      package the object is blessed into. If "REQUIRE" is given then it will
      do a comparison and die if the package version is not greater than or
      equal to "REQUIRE".

      "VERSION" can be called as either a static or object method call.

  The "isa" and "can" methods can also be called as subroutines

  UNIVERSAL::isa ( VAL, TYPE )
      "isa" returns true if one of the following statements is true.

      ·	      "VAL" is a reference blessed into either package "TYPE" or a
	      package which inherits from package "TYPE".

      ·	      "VAL" is a reference to a "TYPE" of Perl variable (e.g.
	      'HASH').

      ·	      "VAL" is the name of a package that inherits from (or is
	      itself) package "TYPE".

  UNIVERSAL::can ( VAL, METHOD )
      If "VAL" is a blessed reference which has a method called "METHOD",
      "can" returns a reference to the subroutine.   If "VAL" is not a
      blessed reference, or if it does not have a method "METHOD", undef is
      returned.

  These subroutines should not be imported via "use UNIVERSAL qw(...)".	 If
  you want simple local access to them you can do

    *isa = <!>UNIVERSAL::isa;

  to import isa into your package.

Index for Section 3

Alphabetical listing for U

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