DSSP
DSSP (Dialog System for Structured Programming) is a programming language designed for Setun. It was created by students in the laboratory of Nikolay Brusentsov at the Computer Science department of the Moscow State University in 1980. The 32-bit version was created in 1989.
DSSP is similar to the Forth programming language; both are examples of stack-based languages. It may be seen as an early fork from Forth, yet with roots extending to the ternary logic computers like Setun.
Relying on the principle of "one word of text - one word of machine code", DSSP stays very close to the actual machine in structure. It uses Reverse Polish Notation, which is a stack-oriented form of calculating.
The first document in English regarding this obscure language distinguishes DSSP from Forth in the following manner: "DSSP was not invented. It was found. That is why DSSP has not versions, but only extensions. Forth is created by practice. DSSP is created by theory. It is not a word."
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