The marshaling library converts collections of Ruby objects into a byte stream, allowing them to be stored outside the currently active script. This data may subsequently be read and the original objects reconstituted. Marshaling is described in the section “Marshalling and Distributed Ruby.” Some objects cannot be dumped: if the objects to be dumped include bindings, procedure objects, instances of class IO, or singleton objects, a TypeError will be raised. If your class has special serialization needs (for example, if you want to serialize in some specific format), or if it contains objects that would otherwise not be serializable, you can implement your own serialization strategy by defining two methods, _dump and _load:
| Method Type | Signature | Returns |
|---|---|---|
| Instance | _dump(aDepth) | Returns a String |
| Class | _load(aString) | Returns a reconstituted Object |
The instance method _dump should return a String object containing all the information necessary to reconstitute objects of this class and all referenced objects up to a maximum depth of aDepth (a value of -1 should disable depth checking). The class method _load should take a String and return an object of this class.
String. If limit is specified, the traversal of subobjects will be limited to that depth. If limit is negative, no checking of depth will be performed.
class Klass
def initialize(str)
@str = str
end
def sayHello
@str
end
endo = Klass.new("hello\n")
data = Marshal.dump(o)
obj = Marshal.load(data)
obj.sayHello → "hello\n"IO or an object that responds to to_str. If proc is specified, it will be passed each object as it is deserialized. Marshal::load.Extracted from the book "Programming Ruby - The Pragmatic Programmer's Guide"
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