I've started to conceive of TLoL (the Language of Languages) as colonies of specialized languages which may use the output of and modify each of the other languages.
XML would act as TLoL's Declarative language, describing how things maybe declared in TLoL. (or something like XML)
Something like Pyrotex's HLL might exist as the operator language, defining the behavior of TLoL's operators.
Some form of

-Calculus language would form the functional language, defining the behavior of TLoL's functions.
XML, HLL, and

-Calculus language might be extended into an object-oriented language which would define the behavior and properties of objects in TLoL.
I envision making use of imperative/state, procedural, genetic, and structural (describes data structures) dialects to handle the specialized applications of TLoL.
The trick of the language would be to identify the context of a phenomena--problem or solution--via pattern recognition, and once so identified, evolve the expression of that phenomena towards a family of more ideal phenomena via rewriting/gene-hacking. Express a phenomena using the best suited set of languages and develop languages to express new phenomena.
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