Traits: experience with a language feature

ABSTRACT

This paper reports our experiences using traits, collections of pure methods designed to promote reuse and understandability in object-oriented programs. Traits had previously been used to refactor the Smalltalk collection hierarchy, but only by the creators of traits themselves. This experience report represents the first independent test of these language features. Murphy-Hill implemented a substantialmulti-class data structure called ropes that makes significant use of traits. We found that traits improved understandability and reduced the number of methods that needed to be written by 46%.

REFERENCES

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• 3: Andrew P. Black , Nathanael Schärli , Stéphane Ducasse, Applying traits to the smalltalk collection classes, Proceedings of the 18th annual ACM SIGPLAN conference on Object-oriented programing, systems, languages, and applications, October 26-30, 2003, Anaheim, California, USA
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INDEX TERMS

Primary Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.3 Coding Tools and Techniques
          Subjects: Object-oriented programming

Additional Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.3 Language Constructs and Features
          Subjects: Inheritance; Classes and objects

General Terms:
Design, Languages

Keywords:
inheritance, reuse, ropes, smalltalk, traits