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,
|Class||_load(aString)||Returns a reconstituted
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 end
o = Klass.new("hello\n") data = Marshal.dump(o) obj = Marshal.load(data) obj.sayHello → "hello\n"
IOor an object that responds to
to_str. If proc is specified, it will be passed each object as it is deserialized.
Extracted from the book "Programming Ruby - The Pragmatic Programmer's Guide"
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