storage::property(3)

NAME

OLE::Storage::Property - maintain Properties for
OLE::Storage::Var

$Revision: 1.1.1.1 $ $Date: 1998/02/25 21:13:00 $

SYNOPSIS

OLE::Storage and OLE::PropertySet are returning from time
to time a kind of variables called Properties ($Prop).
Properties could be handled as follows:
 sub work {
    my $Prop = shift;
    if (is_scalar $Prop) {
       do_something_with ($Prop); # $Prop definitively  is
a scalar.
    } else {
       foreach $P (@{array $Prop}) {
          work  ($P);               # $P could be an array
itself.
       }
    }
 }
$string = $Prop -> string()
$NewProp = $OldProp -> cast (""string"")

DESCRIPTION

OLE::Storage::Property is maintaining the Properties, that
are initially instantiated by other packages. It gives
storage places to OLE::Storage::Var, manages Property to
Property conversions, Property to scalar conversions and
type information. Though you will use the member functions
of OLE::Storage::Property quite often, you should never
create a Property directly with this package. Therefore
"use OLE::Storage::Property" even was useless.

Type implementation itself is done at OLE::Storage::Var,
that offers some private methods for OLE::Storage::Prop
erty. Both, type conversions and type availability are
quite far from being complete (as you will notice when
looking at Var.pm). For this release I cared only to have
the something->string conversions working, and therefore
only them are documented above.

array

_@Properties = $Prop -> array()

Returns a reference to a Property list. You have to
use this to find out, which properties are hiding
inside an array property.

Conversion: Property to perl scalar

$scalar = $Prop -> method()

Returns a scalar variable, that perl understands.
Momentarily method() should be string() only.

Conversion: Property to Property

$NewProp = $OldProp -> cast (""method"")

Returns a Property of type "method".

is_scalar

1||0 == $Prop -> is_scalar()

Returns 1 if $Prop is a scalar variable, 0 otherwise.
A property is scalar, if it is not an array.

is_array

1||0 == $Prop -> is_array()

Returns 1 if $Prop is some array variable, 0 other
wise.

is_varray

1||0 == $Prop -> is_varray()

Returns 1 if $Prop is a variant array variable, 0 oth
erwise. A variant array is an array, that consists out
of elements with different types.

stype

$type = $Prop -> stype()

Returns the scalar type of property $Prop. This is
useful if $Prop is an array and you want to know, what
kind of variables it consists of.

type

$type = $Prop -> type()

Returns the type of the Property. It is a number if it
is a real property type, and it is a string, if it is
an internal property type.

typestr

$typestr = $Prop -> typestr()

Returns the name of the property type as string.

KNOWN BUGS

Property handling is very slow.

SEE ALSO

OLE::Storage::Var, demonstration program "ldat"

AUTHOR

Martin Schwartz <schwartz@cs.tu-berlin.de>.

perl v5.8.0 1998-02-25 Storage::Property(3)