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If it does then a reference to the sub is returned. If it does not then \fIundef\fR is returned. This includes methods inherited or imported by \f(CW$obj\fR, \f(CW\*(C`CLASS\*(C'\fR, or \&\f(CW\*(C`VAL\*(C'\fR. .Sp \&\f(CW\*(C`can\*(C'\fR cannot know whether an object will be able to provide a method through \s-1AUTOLOAD\s0, so a return value of \fIundef\fR does not necessarily mean the object will not be able to handle the method call. To get around this some module authors use a forward declaration (see perlsub) for methods they will handle via \s-1AUTOLOAD\s0. For such 'dummy' subs, \f(CW\*(C`can\*(C'\fR will still return a code reference, which, when called, will fall through to the \s-1AUTOLOAD\s0. If no suitable \s-1AUTOLOAD\s0 is provided, calling the coderef will cause an error. .Sp \&\f(CW\*(C`can\*(C'\fR can be called as a class (static) method, an object method, or a function. .Sp When used as a function, if \f(CW\*(C`VAL\*(C'\fR is a blessed reference or package name which has a method called \f(CW\*(C`METHOD\*(C'\fR, \f(CW\*(C`can\*(C'\fR returns a reference to the subroutine. If \f(CW\*(C`VAL\*(C'\fR is not a blessed reference, or if it does not have a method \&\f(CW\*(C`METHOD\*(C'\fR, \fIundef\fR is returned. .IP "\s-1VERSION\s0 ( [ \s-1REQUIRE\s0 ] )" 4 .IX Item "VERSION ( [ REQUIRE ] )" \&\f(CW\*(C`VERSION\*(C'\fR will return the value of the variable \f(CW$VERSION\fR in the package the object is blessed into. If \f(CW\*(C`REQUIRE\*(C'\fR is given then it will do a comparison and die if the package version is not greater than or equal to \f(CW\*(C`REQUIRE\*(C'\fR. .Sp \&\f(CW\*(C`VERSION\*(C'\fR can be called as either a class (static) method, an object method or or a function. .PP These subroutines should \fInot\fR be imported via \f(CW\*(C`use\ UNIVERSAL\ qw(...)\*(C'\fR. If you want simple local access to them you can do .PP .Vb 1 \& *isa = \e&UNIVERSAL::isa; .Ve .PP to import isa into your package.