Aggregate pattern: Difference between revisions

Revision as of 08:58, 29 December 2007

Revision as of 09:02, 29 December 2007

Line 8:

== Computer programming ==

{{Expand-section|a clear explanation of the code example or adding another code example|date=October 2007}}

In [[Design Patterns]], an aggregate is not a design pattern but rather refers to an object such as a list, vector, or generator which provides an interface for creating [[iterator]]s. The following example code is in [[Python (programming language)|Python]].

Line 46 ⟶ 44:

</pre>

Python hides essentially all of the details using the [http://www.python.org/doc/lib/typeiter.html iterator protocol]. Confusingly, [[Design Patterns]] uses "aggregate" to refer to the blank in the code <code>for x in ___:</code> which is unrelated to the term "aggregation" <ref>[[Design Patterns]], p. 22: "Aggregation implies that one object owns or is responsible for another object. ... Aggregation implies that an aggregate object and its owner have identical lifetimes."</ref>. Neither of these terms refer to the statistical aggregation of data such as the act of adding up the Fibonacci sequence or taking the average of a list of numbers.

== References ==

<references/>

== See also ==