Prototype-based languages are classless object-oriented languages, OO without classes. Instances of objects are made by cloning other instances. Usually, these languages have only one data structure, the associative array. Such languages are very flexible during runtime, and far simpler than class-based languages. The original one was Self.
OO prototype-based, reflective language, based on only message passing, a key trait of OO languages; it allows late-binding polymorphism, the key trait making possible incremental modifying of programs. Descriptions, papers, implementations: Smalltalk, C++, Java, Scheme; MiniMix.
An article for PIE Developers magazine describing a technique for structuring a NewtonScript program using class-like objects.
Language with interactive development environment, supports multiple views per object, bytecode VM; was user programming environment of EO communicator; description, PDF manuals. By Mark Lentczner.
Was Poe: prototype inheritance language and OO virtual machine for building network-accessible programs for multiple programmers, users, agents. Persistence and garbage collection are automatic and transparent. [Open Source, GPL]
Growing article, with links to many related topics. [Wikipedia]
Brief description with many forum comments. [Slashdot]
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