Ten15
Ten15 is an algebraically specified abstract machine. It was developed by Foster, Currie et al. at the Defence Evaluation and Research Agency at Malvern, England, during the 1980s. It arose from earlier work on the Flex machine, which had an architecture with a microcode capability .
Ten15 served as an intermediate language for compilers, but with several unique features, some of which have still to see the light of day in everyday systems. Firstly, it was strongly typed, yet wide enough in application to support most languages - except C, which ultimately led to its development into ANDF and TDF. Secondly, it offered a persistent, write-only filestore mechanism, allowing arbitrary data structures to be written and retrieved without conversion into an external representation.
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