Stack (abstract Data Type) - Abstract Definition

Abstract Definition

A stack is a basic computer science data structure and can be defined in an abstract, implementation-free manner, or it can be generally defined as a linear list of items in which all additions and deletion are restricted to one end that is Top.

This is a VDM (Vienna Development Method) description of a stack:

Function signatures:

init: -> Stack push: N x Stack -> Stack top: Stack -> (N U ERROR) remove: Stack -> Stack isempty: Stack -> Boolean

(where N indicates an element (natural numbers in this case), and U indicates set union)

Semantics:

top(init) = ERROR top(push(i,s)) = i remove(init) = init remove(push(i, s)) = s isempty(init) = true isempty(push(i, s)) = false

Read more about this topic:  Stack (abstract Data Type)

Famous quotes containing the words abstract and/or definition:

    The more abstract the truth you wish to teach, the more you need to seduce the senses to it.
    Friedrich Nietzsche (1844–1900)

    ... if, as women, we accept a philosophy of history that asserts that women are by definition assimilated into the male universal, that we can understand our past through a male lens—if we are unaware that women even have a history—we live our lives similarly unanchored, drifting in response to a veering wind of myth and bias.
    Adrienne Rich (b. 1929)