instance


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Related to instance: Instance variable, Database instance

instance

Logic
a. an expression derived from another by instantiation
b. See substitution

instance

(programming)
An individual object of a certain class. While a class is just the type definition, an actual usage of a class is called "instance". Each instance of a class can have different values for its instance variables, i.e. its state.

instance

(1) A single copy of a running program. Multiple instances of a program mean that the program has been loaded into memory several times.

(2) In object technology, a member of a class; for example, "Lassie" is an instance of the class "dog." When an instance is created, the initial values of its instance variables are assigned.
References in classic literature ?
In considering what words mean, it is natural to start with proper names, and we will again take "Napoleon" as our instance.
A poker, for instance, is just a poker; we do not call one "John" and another "Peter.
One instance of walking cannot be concentrated into an instant: it is a process in time, in which there is a causal connection between the earlier and later parts, as between the earlier and later parts of Jones.
For instance, 'white' being present in a body is predicated of that in which it is present, for a body is called white: the definition, however, of the colour white' is never predicable of the body.
For instance, if the characteristic 'terrestrial' is predicated of the species 'man', the definition also of that characteristic may be used to form the predicate of the species 'man': for 'man' is terrestrial.
In the case of secondary substances, when we speak, for instance, of 'man' or 'animal', our form of speech gives the impression that we are here also indicating that which is individual, but the impression is not strictly true; for a secondary substance is not an individual, but a class with a certain qualification; for it is not one and single as a primary substance is; the words 'man', 'animal', are predicable of more than one subject.
Take, for an instance, this description of high-northern summer:--
The New Endymion" is a good instance of such sustained [113] power.
The captain, at Mr Allworthy's instance, was outwardly, as we have said, reconciled to his brother; yet the same rancour remained in his heart; and he found so many opportunities of giving him private hints of this, that the house at last grew insupportable to the poor doctor; and he chose rather to submit to any inconveniences which he might encounter in the world, than longer to bear these cruel and ungrateful insults from a brother for whom he had done so much.
The doctor went directly to London, where he died soon after of a broken heart; a distemper which kills many more than is generally imagined, and would have a fair title to a place in the bill of mortality, did it not differ in one instance from all other diseases--viz.
The great and inherited development of the udders in cows and goats in countries where they are habitually milked, in comparison with the state of these organs in other countries, is another instance of the effect of use.
Nevertheless, as our varieties certainly do occasionally revert in some of their characters to ancestral forms, it seems to me not improbable, that if we could succeed in naturalising, or were to cultivate, during many generations, the several races, for instance, of the cabbage, in very poor soil (in which case, however, some effect would have to be attributed to the direct action of the poor soil), that they would to a large extent, or even wholly, revert to the wild aboriginal stock.