Extempore is a programming language and runtime environment designed with live programming in mind. It supports interactive programming in a REPL style, compiling and binding code just-in-time. Although Extempore has its roots in ‘live coding’ of audiovisual media art1, it is suitable for any task domain where dynamic run-time modifiability and good numerical performance are required. Extempore also has strong timing and concurrency semantics, which are helpful when working in problem spaces where timing is important (such as audio and video).
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