Slot
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Says whether the Slot acts like a [[FinalSlot]] -- successive <code>[[#get/0|get]]()</code>s on the same slot will always give the same value. | Says whether the Slot acts like a [[FinalSlot]] -- successive <code>[[#get/0|get]]()</code>s on the same slot will always give the same value. | ||
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Note that final implies read-only, but read-only does not imply final. | Note that final implies read-only, but read-only does not imply final. | ||
Revision as of 00:06, 24 March 2008
A Slot is an object which provides the behavior of the binding of a noun. "&" in the E language allows working with slots.
A slot can also be considered a zero-dimensional collection, i.e. one which has exactly one element.
Contents |
Notable implementations
Protocol
get/0
get() :any
Returns the current value of this slot.
put/1
Sets the current value to the (possibly coerced) provided value, if appropriate for this type of slot; throws if not allowed.
isFinal/0
isFinal() :boolean
Says whether the Slot acts like a FinalSlot -- successive get()s on the same slot will always give the same value.
Note that final implies read-only, but read-only does not imply final.
readOnly/0
readOnly() :Slot
Returns a facet allowing get/0 but not put/1.
