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eieio: Making New Objects

 
 4 Making New Objects
 ********************
 
 Suppose we have a simple class is defined, such as:
 
      (defclass record ()
         ( ) "Doc String")
 
 It is now possible to create objects of that class type.
 
    Calling ‘defclass’ has defined two new functions.  One is the
 constructor RECORD, and the other is the predicate, RECORD-p.
 
  -- Function: record object-name &rest slots
 
      This creates and returns a new object.  This object is not assigned
      to anything, and will be garbage collected if not saved.  This
      object will be given the string name OBJECT-NAME.  There can be
      multiple objects of the same name, but the name slot provides a
      handy way to keep track of your objects.  SLOTS is just all the
      slots you wish to preset.  Any slot set as such _will not_ get its
      default value, and any side effects from a slot’s ‘:initform’ that
      may be a function will not occur.
 
      An example pair would appear simply as ‘:value 1’.  Of course you
      can do any valid Lispy thing you want with it, such as ‘:value (if
      (boundp 'special-symbol) special-symbol nil)’
 
      Example of creating an object from a class:
 
           (record :value 3 :reference nil)
 
    To create an object from a class symbol, use ‘make-instance’.
 
  -- Function: make-instance class &rest initargs
      Make a new instance of CLASS based on INITARGS.  CLASS is a class
      symbol.  For example:
 
             (make-instance 'foo)
 
      INITARGS is a property list with keywords based on the ‘:initarg’
      for each slot.  For example:
 
             (make-instance 'foo :slot1 value1 :slotN valueN)
 

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