slotUnbound

slotUnbound( 
u_class 
g_object 
s_slotName 
)
=> g_result

Description

This function is called when the slotValue function attempts to reference an unbound slot. It signals that the value of the slot s_slotName of g_object has not been set yet. In this case, slotValue returns the result of the method.

Arguments

u_class	A class object. The class must be either standardObject or a subclass of standardObject.
g_object	An instance of u_class.
s_slotName	The name of the unbound slot.

Value Returned

g_value

Value contained in the slot s_slotName. The default value is '\*slotUnbound\*.

Examples

defclass( A () ((a)))
=> t

x = (makeInstance 'A)
=> stdobj@0x83bf018

defmethod( slotUnbound (class (obj A) slotName) (printf "slotUnbound : slot '%L'is unbound\n" slotName) (setSlotValue obj slotName 6)
)
=> t

x->a
=> slotUnbound : slot 'a' is unbound
=> 6

x->a
=> 6

defmethod( slotUnbound (class (obj A) slotName) (printf "slotUnbound : slot '%L' is unbound\n" slotName) (setSlotValue obj slotName 6)
8
)
=> t

*WARNING* (defmethod): method redefined generic:slotUnbound class:(t A t)

x->a = '\*slotUnbound\*

\*slotUnbound\*

x->a
=> slotUnbound : slot 'a' is unbound
=> 8 ;; the return value of slotUnbound method, not a new value of the slot  

x->a
=> 6

Related Topics

Classes and Instances

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