Connotational subtyping is an approach to typing that allows an object's type to change dynamically, following changes to the object's internal state. This allows for a more precise representation of a problem domain with logical objects that have variable behavior. Two approaches to supporting connotational subtyping in the Ruby programming language were implemented: a language-level implementation using pure Ruby and a modification to the Ruby 1.8.7 interpreter. While neither implementation was wholly successful the language level implementation created complications with reflective language features like self and super and, while Ruby 1.8.7 has been obsoleted by Ruby 1.9 (YARV), the results suggest that Chambers-style, predicate-based runtime type inference could be incorporated into Ruby with only some reduced interpreter performance.
","abstract_html":"<p>Connotational subtyping is an approach to typing that allows an object's type to change dynamically, following changes to the object's internal state. This allows for a more precise representation of a problem domain with logical objects that have variable behavior. Two approaches to supporting connotational subtyping in the Ruby programming language were implemented: a language-level implementation using pure Ruby and a modification to the Ruby 1.8.7 interpreter. While neither implementation was wholly successful the language level implementation created complications with reflective language features like <b>self</b> and <b>super</b> and, while Ruby 1.8.7 has been obsoleted by Ruby 1.9 (YARV), the results suggest that Chambers-style, predicate-based runtime type inference could be incorporated into Ruby with only some reduced interpreter performance.</p>","abstract_has_math":false,"creators":["Dillon, Ian S"],"institution":null,"degree_name":"MS (Master of Science)","degree_level":"Thesis - unrestricted","degree_discipline":"Computer and Information Science","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012-12-15T08:00:00Z","date_published":"2012-12-15T08:00:00Z","updated_at":"2026-07-24T02:20:42Z","subjects":["type systems","ruby","class mutability","Computer Sciences","Physical Sciences and Mathematics","Theory and Algorithms"],"languages":[],"rights":["Copyright by the authors."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://dc.etsu.edu/etd/1497","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Dillon, Ian S"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2012-12-15T08:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Computer and Information Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - unrestricted"]},{"key":"thesis:degree_name","label":"Degree Name","values":["MS (Master of Science)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["type systems","ruby","class mutability","Computer Sciences","Physical Sciences and Mathematics","Theory and Algorithms"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Copyright by the authors."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://dc.etsu.edu/context/etd/article/2690/viewcontent/DillonI111612f.pdf","https://dc.etsu.edu/etd/1497"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Connotational subtyping is an approach to typing that allows an object's type to change dynamically, following changes to the object's internal state. This allows for a more precise representation of a problem domain with logical objects that have variable behavior. Two approaches to supporting connotational subtyping in the Ruby programming language were implemented: a language-level implementation using pure Ruby and a modification to the Ruby 1.8.7 interpreter. While neither implementation was wholly successful the language level implementation created complications with reflective language features like self and super and, while Ruby 1.8.7 has been obsoleted by Ruby 1.9 (YARV), the results suggest that Chambers-style, predicate-based runtime type inference could be incorporated into Ruby with only some reduced interpreter performance.
"]},{"key":"dc:title","label":"Title","values":["Connotational Subtyping and Runtime Class Mutability in Ruby"]}]}],"canonical_facts":{"dc:creator":["Dillon, Ian S"],"dc:date.issued":["2012-12-15T08:00:00Z"],"dc:description.abstract":["Connotational subtyping is an approach to typing that allows an object's type to change dynamically, following changes to the object's internal state. This allows for a more precise representation of a problem domain with logical objects that have variable behavior. Two approaches to supporting connotational subtyping in the Ruby programming language were implemented: a language-level implementation using pure Ruby and a modification to the Ruby 1.8.7 interpreter. While neither implementation was wholly successful the language level implementation created complications with reflective language features like self and super and, while Ruby 1.8.7 has been obsoleted by Ruby 1.9 (YARV), the results suggest that Chambers-style, predicate-based runtime type inference could be incorporated into Ruby with only some reduced interpreter performance.
"],"dc:identifier":["https://dc.etsu.edu/context/etd/article/2690/viewcontent/DillonI111612f.pdf","https://dc.etsu.edu/etd/1497"],"dc:rights":["Copyright by the authors."],"dc:subject":["type systems","ruby","class mutability","Computer Sciences","Physical Sciences and Mathematics","Theory and Algorithms"],"dc:title":["Connotational Subtyping and Runtime Class Mutability in Ruby"],"thesis:degree_discipline":["Computer and Information Science"],"thesis:degree_level":["Thesis - unrestricted"],"thesis:degree_name":["MS (Master of Science)"]},"updated_at":"2026-07-24T02:20:42Z"}