(goops.info.gz) Instance creation and slot access

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 Instance creation and slot access
 ---------------------------------
 
 Creation of an instance of a previously defined class can be done with
 the `make' procedure. This procedure takes one mandatory parameter
 which is the class of the instance which must be created and a list of
 optional arguments. Optional arguments are generally used to initialize
 some slots of the newly created instance. For instance, the following
 form
 
      (define c (make <complex>))
 
 will create a new `<complex>' object and will bind it to the `c' Scheme
 variable.
 
 Accessing the slots of the new complex number can be done with the
 `slot-ref' and the `slot-set!'  primitives. `Slot-set!' primitive
 permits to set the value of an object slot and `slot-ref' permits to
 get its value.
 
      (slot-set! c 'r 10)
      (slot-set! c 'i 3)
      (slot-ref c 'r) => 10
      (slot-ref c 'i) => 3
 
 Using the `describe' function is a simple way to see all the slots of
 an object at one time: this function prints all the slots of an object
 on the standard output.
 
 First load the module `(oop goops describe)':
 
      `(use-modules (oop goops describe))'
 
 The expression
 
      (describe c)
 
 will now print the following information on the standard output:
 
      #<<complex> 401d8638> is an instance of class <complex>
      Slots are:
           r = 10
           i = 3
 

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(goops.info.gz) Class hierarchy and inheritance of slots

(goops.info.gz) Inheritance

(goops.info.gz) Slot description