/ 
OLE-Storage-0.381
River stage zero No dependents
/ OLE::Storage::Property

NAME

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

$Revision: 0.3.8.1 $ $Date: 1997/10/25 01:15:02 $

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::Property. 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 otherwise.

is_varray

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

Returns 1 if $Prop is a variant array variable, 0 otherwise. 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>.