ObjectSpace :: isValid - Is object space handle valid?
An object space handle is valid, when it has been opened successfully, i.e. when it refers to a valid access object.
Return value: Success ( bool )
The value is true when the function was executed successfully. Otherwise the value is set to false.
Implementation details
bool
ObjectSpace  :: isValid (  )
The function returns true, when the object space handle refers to a valid access object and false otherwise.
In order to avoid exceptions for invalid object space handles, this function can be used for checking the valid state before calling critical functions.