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(slib.info)Yasos interface

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Enter node , (file) or (file)node

Interface
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 - Syntax: define-operation `('opname self arg ...`)' DEFAULT-BODY
     Defines a default behavior for data objects which don't handle the
     operation OPNAME.  The default behavior (for an empty
     DEFAULT-BODY) is to generate an error.

 - Syntax: define-predicate opname?
     Defines a predicate OPNAME?, usually used for determining the
     "type" of an object, such that `(OPNAME? OBJECT)' returns `#t' if
     OBJECT has an operation OPNAME? and `#f' otherwise.

 - Syntax: object `((NAME SELF ARG ...) BODY)' ...
     Returns an object (an instance of the object system) with
     operations.  Invoking `(NAME OBJECT ARG ...' executes the BODY of
     the OBJECT with SELF bound to OBJECT and with argument(s) ARG....

 - Syntax: object-with-ancestors `(('ancestor1 init1`)' ...`)'
          operation ...
     A `let'-like form of `object' for multiple inheritance.  It
     returns an object inheriting the behaviour of ANCESTOR1 etc.  An
     operation will be invoked in an ancestor if the object itself does
     not provide such a method.  In the case of multiple inherited
     operations with the same identity, the operation used is the one
     found in the first ancestor in the ancestor list.

 - Syntax: operate-as component operation self arg ...
     Used in an operation definition (of SELF) to invoke the OPERATION
     in an ancestor COMPONENT but maintain the object's identity.  Also
     known as "send-to-super".

 - Procedure: print obj port
     A default `print' operation is provided which is just `(format
     PORT OBJ)' (Note: Format) for non-instances and prints OBJ
     preceded by `#<INSTANCE>' for instances.

 - Function: size obj
     The default method returns the number of elements in OBJ if it is
     a vector, string or list, `2' for a pair, `1' for a character and
     by default id an error otherwise.  Objects such as collections
     (Note: Collections) may override the default in an obvious way.